Flickering screen

Ok, so I've been a happy owner of the iPad since the international launch day. Last weekend the screen started flickering, and the guy had been crashing out to the apple logo frequently despite hard resets so I decided to restore the software. Fixed the crashing but the screen was still flickering so I got on the blower to apple support.

I've got an appointment this Friday to get it swapped out but after reading all the horror stories about dusty screens and light bleeding I'm having second thoughts. It hasn't done the flickering all week so I'm wondering if it was something to do with the light conditions at that particular time and the auto brightness? Has anyone else had this happen to them? What's your view?

I should probably add I don't mean flickering like a refresh rate flicker, but the screen actually going completely black and coming back a moment later.