I have the iPhone 2+3g. I've had 3 blackberries and now have the Pre. I LOVE this phone!
1) WAY better reception for me on Sprint than AT&T and the iPhone! (Note, iPhone has the apps and a great media player, and if it had better reception, i would've stayed).
2) Multitasking is AWESOME!
3) HTML Emails look beautiful.
4) New App store will make this phone complete.
5) FAR better Web Browser
My only issues with this Pre is that this is my 4th one. Sigh, this is making me second guess it only because of the hardware issues. The keyboard is cramped. My only issues.
Other than that, the Pre is an excellent phone!
Try it out for 30 days, though.