I was one of those unfortunate people who recently upgraded my HTC ThunderBolt to the Gingerbread update. I should have waited, but I pressed the button a few weeks ago that updated the Android OS to 2.3.4.
My phone has been acting very funny. The phone was very sluggish and my contacts were not appearing. The 4G LTE would often disconnect and I finally got to the point where I did a factory reset to see if that would fix some of these problems.
The HTC ThunderBolt has been plagued with faulty ROMs that have caused problems. The latest ROM update supposedly has some problems associated with the voice mail notification, but that's probably not an issue for me since I use Google Voice. The sluggish performance and the disconnections from the network were my main problems. I've been tempted to flash a custom ROM on this device, but I just don't have the time these days to do that. For now, I'll see how the next few weeks go. I'm hoping that the hard factory reset will solve my main problems.