Here are the options Ford had to choose from and I think they made the right choice. Ya'll ought to be excited that Ford is putting a performance tuned version of this engine in the Raptor.
6.2L V8
411 hp @ 5,500 rpm
Torque:
434 lb-ft @ 4,500 rpm
3.5L V6 II
~450 hp @ ~5,500 rpm
Torque:
~470 lb-ft @ ~ 1,700 rpm
Raj Nair already stated the Raptor will be at least 450 hp.
If you want sound, buy a boom box and play sucky HEMI sounds out the rear window and take pictures of your friends smiling.
I will take performance, regardless of how it sounds. If you don't like it don't buy one, go get yourself a dodge "Power Wagon."