I think this is good, so don't take my thoughts the wrong way here, but...
To me, this is a little too behind the scenes for me. You only get the flag if you type in key words that are symbolic of being homosexual. That means that, in general, only gay individuals will ever see it.
I would be way more happy to see google have something that supports gay people on their front page. I would prefer it not be the rainbow, cuz that is flaunt..ish to me. Or maybe just say Peace in multi color letters or something down in the corner.
its a good start though
I wonder if Apple is doing anything- they seem to be pretty progressive