My tablet (sgh-i467m) takes fits where the screen stops responding to touch input for 3 or 4 seconds at a time. Whatever is on the screen keeps going on as normal, but tapping the screen does nothing. It happens every minute or so, and sometimes ...
I've had it since Christmas. The guy at the telus shop where we got it knows I've been having this issue since we got it too. Samsung says they've never heard of this problem too (typical).