i went from an '05 thruxtonized bonnie to an '09 streetie a couple months ago, and, yeah, the surge in power once you get over 4000 RPMs is pretty remarkable. The biggest adjustment has been a twitchier throttle (probably primarily due to going to EFI from carbs).
It's a fantastic bike, and I can't wait to really tuck into it when I get it out of the garage in the Spring.