Microsoft announces something they call interoperable parsing in IE9 which apparently means they sometimes align with WebKit, as it is in released versions of Safari and Chrome today, and sometimes with HTML5. WebKit development builds meanwhile have aligned with HTML5. Funny.
The real “What The Fuck” here though is them recommending that everyone should go ahead and use their own “generic elements.” Your site will be more semantic for it! This was a bad idea in 2005 and it still is today. In fact, for HTML it is even worse, as it means your generic elements — that will have the semantic meaning of the span element — might clash with HTML as we add more elements to browsers in the future. Use the class attribute.