It does get warm! I'm running Fresh 2.3.3. After about 10 minutes of tethering, the last time I used the wireless tether, the notification light started blinking alternately green and amber, while it was plugged into the laptop. I pulled the battery cover off, (while continuing to tether) and it quickly stopped blinking. I never checked the battey temp, and I don't know what temperature triggers this "warning". This was about 6 weeks ago, and I have seen no obvious issues. Previous tether sessions didn't display this warning...