Are there any difference between "early" Piledriver and "late" Piledriver in terms of execution? There should not be.
20h+ Models AGLUs include execution of these instructions:
BEXTR reg, reg, reg
MOV reg, reg
XADD reg, reg
XCHG reg32, reg32
XCHG reg64, reg64
^-- Late Piledriver, Early Steamroller, and newer etc.
Other than Bextr, Mov, Xadd, Xchg being allowed to be executed in the AGLU pipes there is no difference between Early Piledriver and Late Piledriver
But, Only Late Piledriver will be getting an IPC increase(4 64bit Movs per clock vs 2 64bit Movs per clock)
But mov is supposedly very important in x86 as it is the most used instruction: http://www.strchr.com/media/top20_instructions_x86.png
If you mean execution as marketing then I would rather wait for February 2nd before I determine my actual answer
Are we heading towards different types of x86 cores inside APUs and CPUs? K10.5+ "Husky" is different from Phenom, but it is clearly does not have Bulldozer features (except, maybe, when it comes to power consumption).
No, all new APUs and CPUs will have Bulldozer Family Cores...Llano was just a stop gap and there is only one version that reached design goals for Llano actually which is the A8-3870 Black Edition
"Early" Piledriver -> "Early" Steamroller -> "Early" Excavator
Bulldozer -> "Late" Piledriver -> "Late" Steamroller -> "Late" Excavator
Bulldozer -> Piledriver v1 + GPU -> Piledriver v2 + No GPU -> Steamroller v1 + GPU -> Steamroller v2 + No GPU -> etc.