Actually, the major browser vendors support parts of it. There is no browser (AFAIK) that supports the entire spec.

>In general I agree completely with you and Bill about this. In this case I think it is mitigated by the W3C being famously slow moving. I don't think anyone expects the HTML5 standard to change in any substantial way between now and final ratification. All the major browser vendors already support it. If they'll take that chance, so would I.