Wireless performance has been solid. Admittedly, my previous phone was a 1xRTT Sprint rig, not an EV-DO phone, but my work phone is EV-DO. Is EV-DO faster? Certainly. Is AT&T's new "Uber-EDGE" better than what people thought it would be? Without a doubt. It's definitely fast enough for email, and even web browsing doesn't return you to the halcyon days of 56K dialup. The iPhone is quite agressive about finding and using Wi-Fi when possible, and the battery life, thus far, has been complaint-free for me. It moves well between EDGE, open Wi-FI, and WPA2 WiFi. No real problems at all there.
Mac and PC Installation Hell: Just Say No
Top 10 Mac Productivity Enhancements
iPhone and Steve Ballmer
Using Vista and Linux on a Mac, Part One
But what about the most important thing, namely, is it a good phone? For me, so far, it's a clear "yes" with the one caveat that applies to any phone: Coverage quality. AT&T's coverage in the land of Sprint, aka Kansas City, MO, is not as nice as I'd like it to be. (Then again, Sprint's not perfect either, and I should be picking up Sprint signals in my fillings here.) But it's not completely horrid either. As far as voice quality, it's fantastic. Clear as day, even when I'm losing coverage. According to my fiance, this is the first time I've talked to her on my cell where she had to look at the caller ID to tell I was on a cell phone. If AT&T can get their coverage improved, then I'll be an even happier scooter.
The thing I keep coming back to with my grand not-yet-three-days of use is this: It.Just.Works. It has had absolutely no rude surprises, no unexpected data loss, nothing. It is literally the best smartphone I have owned, and I've been living that life since 2001. It's pretty, with a great UI, and a lot of care taken to making the cell phone experience not suck, and I can tell you that for me at least, the iPhone is proof that you can get people to use a phone because of the design, not in spite of it.