Andy_Langton - 10:55 pm on May 2, 2012 (gmt 0)
Let's not turn this into a Google-bashing thread. They're volunteering coding practices that are likely to be easier for them to interpret - and help you rank. You can, of course, write your code any way you choose. But this is an SEO forum, and SEO is involves changing a site to get it to rank better.
Some interesting bits and pieces in there too. Ditch type attributes? No entity references?
The W3C specs reigned supreme for SEO prior to HTML5 where IMO they dropped the ball. Perhaps Google want to be a contender now?