The Weather Channel app is nicer than the stock weather app.
Pandora is nice if you want to listen to music outside of your playlist (but it streams over wifi, and can suck your battery down)
Facebook if you use Facebook
Quoted:
The Otterbox is awesome. Pandora is the app to get being free radio without no commercials. And what I have been telling people as a developer is wait until July for the third incarnation of the iphone. It resolves a few issues that are with the iphone. Plus it will be able to run background apps. A more powerfull processor and a few other additions I cannot speak of yet. If you have the iphone now the 3.0 software will enable mms and a few other things that needed to be in the original software.
I'm really curious about the new hardware, but will be stuck with my 3G for a while. I picked it up last October, so maybe I'll upgrade this October. My phone runs fine, but sometimes the battery life blows and (it's jailbroken, so I know that contributes) it's often sluggish.
I would really like to see improved battery life and a faster processor. I've read a bit about the 3.0 OS update, and it sounds like they're FINALLY resolving many lacking features.