Wow.  That probably answers questions we haven't even thought to ask yet.  But looking at the "normalized frequency" versus power-per-module chart (assuming module = "core pair") tells quite the story about why Carrizo got bumped off FM2+.  Carrizo's HDL voltage scaling past ~23W per module is inferior.  That means, 45W Carrizo would probably reach the same clocks as an A8-7600 (guesstimate).  
The second slide seems to contradict itself.  What do they mean, double-digit increases in performance when the IPC increase is only 5%? Granted, you have to take promises of IPC with a grain of salt.  Having witnessed Kaveri exhibit some odd performance characteristics, it is probable that Excavator will make gains in some areas and not in others.  That 5% is probably just an average.
I will say this much, Carrizo will probably be much cheaper to produce with area reduction like that.  Funny that the cache block isn't reduced at all.