[Mbai2]

It hasn't happened yet on my Evo and it may or may not be a bug. If it is indeed as your guys describe, it just may be something inherent to the design of the capacitive screen. Unlike resistive screens that create their own loop, these screens use you finger as a conductive device to create a loop. If the your finger is too dry, you may not have enough conductive surface area to complete the circuit unless you press hard enough to flatten your finger tip. When you are laying it on a "non-conductive surface," you are actually just laying it on a slicker surface so you aren't pressing as hard on the screen because the phone would just slip around if you did. Less finger surface area touches the screen, the circuit doesn't complete, the screen doesn't respond. Next time this happens, try pressing slightly firmer on the screen or lick/wet your finger tip (for testing only; not recommended for normal use) to see if it solves it.