For those with random REBOOT issues on Thunderbolt after the OTA latest update: Remove/delete the app that switches between 4G & 3G, & manually reboot. This should address the issue.
The app is the same as the key combo to get to the settings page, right? At any rate, I have switched mine back from the CDMA auto (PRL) to the stock setting (CDMA LTE). I will see if that makes any difference.
I have had terrible performance since upgrade. As in a few reboots and from 100% battery at 7am to 20% at 11am. I had one reboot today that dropped me 12% battery life!!
Another site said that some of this is dependent on your local towers and I hear Indianapolis (where I am) is doing a lot with their towers as 4G is about to be unleashed. I have read of others with lots of reboots here.
I will report back.