I’ve had problems with my new iPad, where the screen would flicker when the brightness was set to a low setting. Very irritating. My first fear was hardware problems but after upgrading to the latest beta version of iOS, 4.2 beta 2 the problem is fixed! Yay! No need to replace my beloved iPad.
**Update** A bit too fast, the problem remains.

So it's back to returning the unit to Apple for an replacement.
maybe it will be fixed in the final version..