As many people have experienced random shutdowns, I too used to have them. Sometime everyday and few other times, more than once a day. I could not figure out why (and I don't know even now the real reason). There are few apps that I run always like e-mail, facebook, launcherPro etc., And there are other apps I run only once in a while like browser. So there was no one app that I could pin point as the cause of this random shutdowns. So I decided to try one by one to see if I can figure out anything, if anything at all. So about 10 days ago, I decided to switch back to TouchWiz UI from LauncherPro (free edition) and see if it make any difference. May be a coincidence, since that switch I have not seen the shotdown even once and everything seem to be working great. I know, some people using TouchWiz also have reported random shutdowns. But I seem to be having favorable results by switching. As I mentioned, I wanted turnoff apps one by one and see the difference. LauncherPro happened to be the first one I chose (randomly). I like LancherPro very much and want to go back it it but I will wait if there is someone who can make similar switch and report if it made any difference?