I think either a) it's been resolved, b) it wasn't that big of a deal to begin with, or c) a combination of the two.
I exchanged 3 iPad 2's for issues with dust getting under the screen. Not one of the iPad 2's I have had were displaying the light bleed problem, and believe me, I checked them all. I guess they all had it a tiny bit, but I don't think I've ever owned an LCD device that DIDN'T have this problem in at least a small way.
In the end, I think it was a vocal minority having the issue, and some people who never would have even noticed it in the first place started obsessing about it for no reason. Hell, I just went to my friend's house over the weekend to see his new $2500 LED 3D TV, and guess what--when there's no picture on an all black screen, the lighting is uneven. It's the nature of LCDs I'm afraid.