I think that DOOM 4 will be Revealed at Quake Con 2012 for three reasons
Reason number 1: is that John Carmack has stated that they will not show anything of DOOM 4 until Rage will be released, now that Rage has been released its the perfect time to show it.
Reason number 2:is the DOOM 3 BFG edition,obviously to prepare people for DOOM 4.

Reason number 3:is What people probably didn,t notice,when Elder Scrolls Online Rumor apeared in March there was also this
Quite:

The game would also be shown at Quakecon 2012 in August, along with id Software’s Doom 4 and several other titles.



This pretty much confirms it, since the rumor about Elder Scrolls Online announcement apearing in May was correct ,witch was probably leakded by a ZeniMax Online Studios employe to gather HUPE for both games

What do you guys think? Will it be Revealed at Quake Con 2012?

P:S sorry for my bad english

Yes, of course it will be shown at this year's QuakeCon

It was going to be showed last year but they said if they did then it would've overshadowed Rage, and they didn't want that, they wanted Rage to be the highlight.

I can't wait, and I'm glad they've made the D3 BFG Edition, gives us finally something to do while we wait