Thanks to Katie Drake for providing such rumors and Synack for compiling them.
Katie over at HO has "confirmed" that SB's don't count as pistols, ward staves are 2++ in CC only, as well as confirmed the psycannon and incinerator stats
Grey Knights don't get an extra Attack for storm bolters. Really people, come on. Nobody really thinks 20 points for a model packing a force weapon, storm bolter, psychic abilities and a Space Marine statline is really going to get an Attack bonus too... right? Right?
Warding stave is a 2+ Invul in close combat only.
The Grey Knights don't have a lot of heavy duty anti-tank equipment. Things like lascannons, multi-meltas and so on are less common here than with other armies. They make up for it by fielding a ton of weapons that are easily able to suppress enemy vehicles (mostly psycannons as well as things like assault cannons on Stormravens, Land Raiders and even Razorbacks should they wish). It's possible to field multiple units of Henchmen with meltaguns if the player takes Coteaz. Chimeras and Rhinos are as good for Grey Knights as they are for Guard and Marines, so it isn't too difficult to get units into melta range.
So mostly, heavy duty anti-tank will be relatively rare and expensive for Grey Knights due to the platforms that these weapons are mounted on, but Knights can field lots of the slightly less destructive weapons, so it all balances out.
EDIT: Thought I posted this earlier, but the stats for psycannons and incinerators are as follows:
Psycannon
Range 24" S7 AP4 Assault 2 Rending or Range 36" S7 AP4 Heavy 4 Rending
Incinerator
Range Template S6 AP4 Assault 1
I'm glad they decided to settle on these stats for the weapons as it sits in that really good middle ground of being good anti-personal and good anti tank and being the right point cost for it, relative to the squads that will be taking it.
I'm sad that the ignore invun is gone, as it really fit with them fighting daemons, but I suppose the extra S and rending makes up for it, in terms of making the army good against all other armies and not just against Daemons.
Katie doesn't have stats for the psilencer, as she's says she forgot to ask about it. Hopefully she'll ask soon.
Now, if we look at the latest stats and what we know of things so far, I want to cast our minds back to one of the Gk threads a while back, where a unknown, Stinger989 posted some things about GK, which everyone dismissed and turned out to be true:
They will not get bogged down and there is two versions of the dredknight as i have read the first option will run ya removed with a gatling psycannon (heavy 12), and a heavy incinerator gun (fires like a hellhound) and its armed with two dred cca. the second is a dred same as above but also armed with a jump jet which will run removed and can move 12" then once per game it can boost to move 30" but may not assault afterwards.
as reguarding the rumors with upping the armor value that is not going to happen although there is a power that allows the vehicle to negate crew stunned and crew shaken.
Right, so the heavy psycannon could potentially be heavy 12 and the Heavy incinerator will hopefully fire like a hellhound, which will be awesome.
Quote yep cortez can make henchmen troops, so you can get stormtroopers but they are now bs3 and not nearly as good. crusaders with a marine cost and coming with a pw and ss is much more attractive.
the other real winner for henchmen are the humans that come with bolters for 5pts or storm bolters for 7pts at bs 3
other troops are the palidan termies with 2 wounds and a 5++ and can get fnp with the apothicary
pergitor squads with all the extra special weapons can become troops too.
vindicar assassin is 0-3 and have the special rounds that are quite nasty 4d6+rend vs. armor
wound on a 2+
take inv save away for the rest of the game
loses his night fight rule but still has stealth.
psy cannons are str 7 with rending
drednight with gattiling psy cannon is only str 5 but 12 shots.
Above you can see he mentioned stuff that we have now confirmed, so we can speculate that the heavy psycannon is S5 heavy 12.
There is a chance tho, that the gatling psycannon he is talking about is the psilencer, which would fit with another rumour I saw here on warseer a couple days ago, where someone said that the psilencer was like a psycannon, just lower S and higher rate of fire.