The Following is from someone who has apparently got the codex. Seems legitimate to me. So I thought I would share to those who may not have seen it.:
"Firstly an outline and disclaimer. I shall break down the book based on its sections as outlined by the Table of Contents, along with details about just how much of the book each section comprises. Those who want to know the rules, skip to Section 5. I also am stating here and now, that as an artist by trade, I respect my colleagues work, and therefore will provide only vague info on the actual fluff, as well as not provide any pictures. (If this leads to some claiming that I am lying, then that is your opinion, no skin off my back.) If you want further info on such, get the book and support their work. Also, I've left most tactica type opinions to myself, as I’m a casual player, not a competitive one.
Section One: The introduction: The same as every other Codex out there, complete with the “How A Codex Works” section, etc. no surprises here. Just one page, as always. (officially page 3)
Section Two: An introductory fluff about how the Tempestus are chosen and trained, the tests they go through, and what happens if they fail. With information on both Scions and Commissars. A total of 9 pages, full of new fluffy goodness. Only portions of this have been seen elsewhere, and mostly just in the first page. Most excellent.
Section 3: A section dedicated to individual specific Regiments, complete with what I shall call a pin-up page. (A single page dedicated to a short description of the regiment, and an 8 inch tall picture representing their specific color scheme.) As well as individual fluff stories for each of the more famous Regiments. 32 pages of fluff, all new, although as some of the later pages in the pin-ups sections demonstrate, they could have fit 4 regiments to a page for their image section. Several of the ones that are awarded a single page I must feel are doing so simply to take up valuable pages and make the book look bigger, as they don't all get an in depth fluff story.
Section 4: Pages 48-57 are split between the standard Time-line of This Codex pages, as well as the showcase of painted models. A final bit of fluff, and some nice shiny new models to look at, what's not to like?
Section 5: here we get to the meat and potatoes of the book.
A Codex Specific Special Rule “Voice of Command” which makes those with it a 'Junior Officer' who can issue a single order at the start of your Shooting Phase. (Note: cannot be used in close combat, while in a vehicle or building even dedicated transport, falling back, or gone to ground. As before cans till run or shoot after issuing an order.) Also, one can only select other units from the Militarum tempestus codex. (Doesn't even allow orders to Astra militarum without a FAQ) They are still a Leadership test, however double 1's no longer confer an extra Order... instead they cause all further orders in that turn to automatically succeed. (Would be better if there were more officers running around this Codex) Whereas double 6's still prevent any further Orders this turn.
The Orders are as Follows :(Note the lack of First Line Fire! Second Line Fire!)
Directed Firestorm Sanctioned: the unit must shoot, but all fired weapons (no restrictions) are twinlinked for this shooting attack.
Autonomous Fire Sanctioned: The unit must make a shooting attack, all models in the unit gain Preferred Enemy for this attack.
Close Assault Doctrine Sanctioned: The Unit has the Crusader Special Rule for the rest of the turn.
Advance On Target: The unit gains Fleet for the rest of the turn
Suppression Doctrine Sanctioned: the unit must make a shooting attack, all hotshot lasguns and hot shot laspistols can only fire a single shot, but gain the Sniper and Pinning special rules. Also the unit cannot charge in the following Assault Phase.
Elimination Protocol Sanctioned: The unit must fire at a vehicle or Monstrous Creature. All shots fired at said target gain Rending.
The Warlord Traits:
1: Dauntless Commander: The Warlord gains Fearless
2: Grenadier: When throwing frag or Krak grenades, the Warlord has the twinlinked special rule, and when using krak grenades or melta bombs in combat, the warlord gains the Tank Hunter special rule.
3: Intrepid Leader: The Warlord and all units from the Codex: Militarum Tempestus within 12” of the Warlord gain the Stubborn Special Rule.
4: Grav-chute Commandos: All friendly units chosen from Codex:Militarum Tempestus re-roll failed Reserve Rolls if arriving from deep-strike. Also, all units in the same platoon as the Warlord only scatter D6” instead of 2D6”
5: Drill Chief: When firing hot-shot lasguns or hot-shot laspistols, units within 12” of the Warlord can fire an additional 6”, provided they did not move in the preceding movement phase.
6: inspired Commander: The Warlord had +1 Leadership to his Profile (up to a max of 10... which means hopefully you aren't using a Lord Commissar as your Warlord)
Section 6: A short two page bit on how to read the following unit lists, as well as how Formations work. Included is a description of what the Icons in the top left corner of each unit page means, as there is no longer the friendly text of “HQ” or “Troops” listed as separate sections.
The icons are as follows: A skull for HQ. A Triangle for Troops. A Lightning Bolt for Fast Attack. Three skulls with connecting lines for Formations. (Note: an observant onlooker will note the lack of a symbol for Elites or Heavy Support. I have not failed to mention them, the Tempestus don't receive any of either.)
Section 7: in depth information for the units. As there is a lot here, I will summarize and pull out a couple notable points.
HQ Commissars are HQs now, as well as independent characters. They can still be upgraded to Lord Commissars, for the only LD 10 unit in the army. A notable change is how Summary Execution works now. When the unit the Commissar is part of fails a Fear, Morale or Pinning Test, you roll a D6. On a 3+ the owning player chooses which model gets executed. On a 1-2 the opponent player chooses which (excluding the Commissar.) After which the chosen model is removed as a casualty and the unit is treated as having successfully passed the test.
Tempestus Command Squad are the second HQ option. Essentially a Platoon Command Squad with access to the Hot-Shot stuff isntead. Also, the Tempestor Prime is the ONLY MODEL IN THE BOOK with access to the “Voice of Command” special rule... So without him, no Orders. Talk about a big target. On top of that, any friendly unit within 18” of the Tempestor Prime may use his LD 9 for any Fear, morale or Pinning tests. (this is mentioned as the special rule Clarion-Vox net. But does require a vox caster in the squad, although having one provides a re-roll on Order LD tests.) In short, he becomes a lynch-pin, and I'll probably be running two of these guys when I am running this army.
Troops: Scions are the only troops choice, and info on them can be found just about anywhere nowadays.
Fast Attack: Both the Taurox Prime and Valkyrie Assault Carrier.
The Valk has not changed much, 25 points more expensive base, but lascannon upgrade is only 10 points, as is the multiple rocket pods upgrade. The heavy bolters are the same. Can also still be taken in squadrons of 3.
The Prime is as noted elsewhere on the internet. It has two fire points on each of its sides. And the upgrades are as follows. Battle cannon can be replaced with a Twinlinked Gatling cannon or 10 points, or a missile launcher for 20. The twinlinked hotshot volley gun can be replaced by a twinlinked autocannon for free.
Formations: There's a ground attack and an Air-attack. Each require a Commissar, Tempestus Command Squad, 3 Scion squads, and four of their specific transport. (Valks for Air, Taurox for land). They both require the Commissar to be joined to one of the units at game start, and for the respective units to embarked on the transports at game start. (So for the air attack the entire formations tarts off the table. And for the ground they must either all start on the table or off the table. No splitting.) If rolling for reserves for the formation, one roll is made for the entire formation, and can be re-rolled. (Whether successful or failed.. Allowing one to have more choice when they arrive.) Bringing the entire formation onto the table at once. Now for the distinctions.
Air Attack: Air Cav special rule makes any units disembarking by grav chute able to re-roll scatter dice. Secure the Area special rule, when a unit disembarks, whether normally or by grav chute, the Valkyrie that was disembarked from gains the Split Fire and Twinlinked special rules for that turn on all its weapons.
Ground Attack: Surgical Deployment. When a unit disembarks from a Taurox, all its weapons gain Pinning and twinlinked until end of turn.
Section 8: the Wargear
All of this can be found elsewhere, as most of it is standard, except for some of the vehicle upgrades, which I shall list here.
Augur Array: When attempting to Deepstrike a unit within 6” of this vehicle, it does not scatter.
Fire Barrels: The first time an enemy attempts to charge this vehicle, that unit suffers D6 S4 AP5 Hits, allocated randomly.
Recovery Gear: If the vehicle is Immobilized, then every subsequent turn it rolls a D6 at the end of the movement phase. On a 6 is it no longer Immobilized, however it does no regain a Hull Point.
Relic Plating: a vehicle with this upgrade has the Adamantium Will Special Rule.
In closing, one will note the lack of any Special Characters, or actual Relics. This is not an oversight on my part, they are also not to be found in the Codex: Militarum Tempestus.
Ultimately, some things I'd have liked to see more of, (like more officers) however, over-all, I'm looking forward to playing this army as-is and see how it goes."
Looks really cool. What do you guys think?