I have this questions too and there doesn't seem to be a general reply, only personal replies:
I have a combination of problems that started before the last 3 updates this past week -yes, 3 updates in 7 days time, without any sort of trauma (dropping on the ground, falling in water, etc).
Problem #1: It started with the yellow-green flicker that I have been reading about.
Problem #2: And sometimes the screen doesn't turn on. Not that the screen doesn't recognize I'm touching it (the bottom buttons light up when I do), but it stays black. I can press the power and home button several times before the screen actually turns on. It's incredibly frustrating, epecially since the reason I got this phone was because my other one did this and I thought it was just dying. Now I see it is possibly a software -updating issue?
What can I do, if anything? I am going to return it otherwise and get an LG or something else.