My wife has a Samsung Haven. She doesn't use it much. There are several times when she goes an entire day without ever using the phone. We've had this phone over a year, and we've noticed it before. Just thought I'd share. Anyway, on those days when she doesn't use the phone, it will just power down for no reason. I try to call her for something important, but can't reach her because she doesn't know the phone is turned off!
Anyone else experience this? I've seen (on this support forum) other complaints about Samsung phones have the same issue. I have a Samsung Zeal and it never powered off by itself. And I've gone several days at a time where I never so much as flipped it open. But it's always stayed on.