Does anybody have any idea why I'm experiencing the issue shown in the picture below? I've tried researching the issue to no avail.

15-Inch MBP (Late 2010)
2.66 GHz Intel Core i7
8GB 1067 MHz DDR3
NVIDIA GeForce GT 330M 512 MB
Mac OS X Lion 10.7.2

Issue: My screen goes from normal color to the darker color (see image) occasionally. Most of the time it happens when I disconnect the dock to my 27-inch Mac display, but sometimes it happens when I wake up my computer and the darkness appears on both my MBP screen and my Thunderbolt display. This has happened both connected and not connected to a power source and I've found the power settings to have no influence on the darker color. Restarting the computer does fix the issue...until it happens again.

As you can see, the background of the top toolbar doesn't change in color. However, the DropBox icon becomes very dark. Background colors to applications change drastically. As you can see, iTunes looks very different. Certain browser pages are too dark to read (e.g. gmail w/ dark background). Skype is so dark that it is almost unusable when this happens.

Anybody experience this? Ideas/thoughts on what to do? It's a pain in the ***, but lugging my MBP/Thunderbolt into a store is such a waste of my time.