To echo Khar, as far as I know, the plans are to maintain the 2010 FAQ, and tweak ship costs/stats where it has been deemed necessary or beneficial by the community across about a decade's (or more) worth of playing to better balance some things. In some cases (Retribution's range being shortened, firepower increased), this has been done to better balance a ship relative to others in its class (like you said, given the option of an Emperor, which was until the FAQs massively undercosted AND nearly matched a Retribution in weight of fire before you even factored in attack craft, or a Retribution, which one ever got fielded?), in other cases, entire fleet lists are getting restructured to make them more playable (Orks), or a major alteration has been made in terms of how the fleet plays in order to make them more balanced/enjoyable to play with (Eldar "move-shoot-move" in the rulebook going to "move-move-shoot").
If you're looking for what's been changed, I'd point you to AfterImageDan's blog, specifically, his BFG:R section:
http://afterimagedan.blogspot.nl/p/as-any-of-you-know-i-am-supporter-and.htmlThings that have survived rounds of debate and voting have made it to the "Finished" list, and things in progress are being discussed on the forums here.