I keep getting reboots from killing things in the multi-tasking bar. Any yes, I realize I don't need to close things there, that not all of them are currently running, that the things are are running aren't really running (depending on the app), and so on. Sometimes I just want to clean it up. I can kill about 10-15, then it locks up and eventually reboots. It doesn't seem to be one particular app that causes the problem, it's very random.
I've also had several instances of something running out of control and eating up all the resources on my phone. My phone get extremely choppy. I'm sure it's a rogue app, but never tracked down which one. It's only happened a few times.
At this point I'm not sure if I should wait for the new software release (still on 4.0) or trade the phone. It seems like a software problem, but I've not heard of anyone else with the same issue and my friends with new phones can't replicate the issue. I could have bad RAM, but I'm really suspecting it's a software issue.