I've never been real thrilled with the whites on my G11. They just ain't white.
There's a few things to consider, though.
If you use a grey screen, as most of us do, that WILL change the look of white. My DIY screen was painted half white, half grey, to compare the difference. In my situation, the whites took on just a tad of yellow shade with the grey screen. Obviously, the grey screen does great things for blacks and contrast.
Then there's the issue of white level settings. We have so many ways to adjust this(projector user settings, Dilard wizard, PC video card, etc.), it can be real confusing sometimes.
I spent hours the other night going back and forth between my modified Dilard black level settings and the original projectors black level settings. The modified setting is what I'll stick with because of the much improved contrast I see, but it comes at the cost of putting a little noise in lighter colors, especially white. I actually see a bit of pink and green blooming(for lack of better term)in some really bright scenes. It's barely noticable, and probably correctable by fine tuning the mod in Dilard. But what I really think is that we need the rest of the Dilard wizards(gamma and 8 Bar)to bring everything together. The Black Level Wizard is just one piece of the puzzle. We need the other pieces. Hint, hint. http://www.avsforum.com/ubb/smile.gif
I use a twin view setup, so when I have my monitor on at the same time as the G11, that's when I really see a difference. In fact, I use the monitor as sort of a test screen for color, contrast and brightness adjusting on the G11. Compared to the monitor, the proper white and grey have been really hard for me to duplicate.
My G11 is not calibrated, BTW. I'd be willing to bet that would make huge improvements, based on recent comments here on the forum.