So a week later I can't say the problem is gone but it's less obvious and definitely not systematic coming from long sleep periods. But it still occurs once in a while, then closing the lid for 10 seconds makes it fine again... I sure hope 10.8.4 fixes this...
I have the same problem with my MBA 13 2010.
I tried reinstalling Mountain Lion but to no avail.
I googled a bit and a very similar problem occurred a couple of years ago that was later fixed with a software update. I also found out that closing the lid for 10 seconds forces a power cycle of the device display and should stop the flickering. It's still annoying but it's marginally faster than a reboot.
I guess we'll just have to wait for a fix to come out eventually from Apple.
So 10.8.4 is out now, the release notes don't mention anything about this issue but I guess it could still be fixed...
I've reset everything, upgraded to 10.8.4 and still getting the flickering. Anyone else still getting this? 😡