Another huge thing is Google Voice I don't use Google Voice for outbound calls, but I absolutely love the voicemail features from Google Voice. I thought that

Another huge thing is Google Voice I don't use Google Voice for outbound calls, but I absolutely love the voicemail features from Google Voice. I thought that visual voicemail on the iPhone was nice, but after switching to Android I realized the combination of the web interface and the onboard voicemail app on the phone is a huge winner. Also, to address the OP's concern about staying on AT&T, my AT&T band N1 seems to work like a champ. If you're not afraid of eBay, then I wouldn't think twice about getting one that would work on AT&T's 3G bands.