In my opinion it'd make close to zero sense for GW to release collective army books which feature several armies in them. After all, let's not forget, GW wants you to shell our your pennies and multiple releases of individual army books work so much better in regards to that than books containing the rules for more than one army.
Just look at the number and frequency of new releases that have been hitting us for the past twelve months or so: More army / codex books in a smaller time frame, more add-on or campaign books, rules
'updates' only made to grab even more coin (looking at you
'Escalation' and
'Stronghold'), plus an overwhelming number of digital releases.
No, it wouldn't make any sense at all for them to release those compilation army books for
WHFB.
Also, I really hope they'll wait 'til 2015 for a release of 9th ed.
WHFB, updating all the armies before releasing a new set of core rules.
And if they're really going to release 7th ed.
40k in 2014 I'm going to throw up .... But I really can't see that rumour coming real at all. Maybe a
40k compilation rulebook containing the core rules, Apocalypse, Escalation and Stronghold, to milk the cow even more. But a new edition of
40k after only two years ... seriously ?
Now, back to the
WHFB army books ...

I sincerly hope (and believe) we'll see Dwarfs, Brets and Wood Elves in 2014, though I'm not entirely sure if Dwarfs or Brets will be first. Yes, Dwarfs are rumoured to hit in january or february, but almost nothing of their model range has vanished from the GW website. Just as opposed to Brets, where a lot of models have allready been taken down the site.
But we'll see ...