I just noticed that Google is now serving it’s homepage with an HTML5 doctype:
I suspect this might have changed when they launched that new fade effect. I also noticed they are doing so when using the new YouTube “Feather” beta. This shouldn’t be too surprising considering their involvement in the HTML5 specs and developing a web browser and announcing it’s moving away from Google Gears.
Of course the pages don’t validate, and don’t really take advantage of much HTML5 features (that I’ve seen at least). But it’s a step in the right direction. With modern browsers like Firefox, Chrome, Safari becoming more popular it’s slowly becoming a reality.