I had a 2000 mustang which I heavily modified up to over 500 hp. It was a lot of fun, and I learned a lot (i.e. spent a LOT of money) about mustangs.

Here's a few sites for Mustang related fun! I'm sure you'll get a lot more information about the new mustangs there than you will here... I used to know a lot more, but that was a couple years ago.

http://www.corral.net/
http://www.stangnet.com/
http://www.fordvschevy.com/
http://www.blueovalnews.com/

Sorry, but I can't give you any specifics myself over 2005+ mustangs except that they look nice.

I will say that having a V8 is a LOT more fun than the V6. But if you're just getting it for a "look at me" car and not a "I wanna have fun stoplight to stoplight" car, then go for the V6... Now, put a TURBO on the V8, and you have stupid fun... man was that stupid...