So its a few months till Android 4.0. The story thus far:
Android 4.0 Features:
-APIs for Tablets and Phones in one sdk version release
-Some minor fixes to OpenGL for gaming
-Refinement of RTS/SIP support introduced in 3.1
-ADT 12 or 13 with support for an sdk installer and source jars support via adt-addons project contributions.
-New version of Webkit.
-Expansion of the UI elements animation APIs introduced with 3.0
-Full C2D release into public promoted form private beta
-Possible FB integration into full android as a message stack(oh and you wanted an android FB device? Well this was FB’s idea negotiate with Google to make it happen :)..its probable and I probably beat TechCrunch to the punch by this little one sentence.)
These are guesses, however most of them are close to what will be in Android 4.0 but some of this could wrong and you should think for yourself.