Mine rebooted randomly before the update, hasn't since.
Same here, hasn't rebooted once since the OTA 2.2 update. I turned it off last week to show someone the new power on graphics and it's been running 144 hours since. I did a hard reset the day before the update so I'm wondering it that's part of why it's been better. I'm re-installing PDANET today to see if that's what was causing it, otherwise the phone has all the same apps that it did before the hard reset.