Mostly, my complaints about Android revolve around issues outside the devices and OS. The market is dreadful, but day-to-day life with the phone is nicer (better notifications, widgets, additional useful functionality, etc.)
iOS5 should close the gap on a lot of this, and it's certainly a more usable OS in a lot of ways. I'm probably committed at this point, but it'll be interesting to see one way or the other.