My DX was being stupid this morning (my first encounter with bugs). My Foursquare was freezing, my screen kept switching between panels and I had a couple random apps open and the tray was randomly opening - kind of like my touchscreen was bugging. I pulled my battery and now going on about 5 hours of bug free use again...
I've never had that. Are you running a task killer by any chance? If so, you could delete it and see if that smooths things out. Otherwise, it's most likely related to some app you have running on the phone.