I had the same experience, except my screen turned magenta, or more specifically, it lost all green, so everything was red, blue, black, or something in between -- hence mostly some flavor of magenta. For those of you who were getting "yellow" screens, were these actually no-blue screens, with everything being red/orange/yellow/green/black? I wonder if anyone's experienced a no-red screen, with everything being blue/cyan/green/black?
Out of curiousity, are any of you who are experiencing this using Go Launcher EX? I installed it not too long before the color glitch.
Also, if this happens to anybody again, it might be a good idea to grab a screen-capture (by holding Home and quickly hitting the Power button). Twould be interesting to see whether the captured image is full color (indicating that the problem is fairly late in the process, perhaps even in the display hardware) or whether captured image is distorted too (indicating that the problem is relatively early in the processing, most likely in software).
Anyway, tis a weird bug, but I was very relieved when it righted itself after about a minute.