This puts Google in a unique position of influence. Imagine if the Googlebot gave even just a hint of priority to sites that validated as XHTML Strict.
I’m not necessarily advocating that, but imagine the impact on web developers! It would help bring standards compliance into the spotlight. Hopefully the resulting discussions would help move the web forward.
If you’re a web developer, rather than worry about reading up on web-standards, just install the Html Validator extension for Firefox and use it as you develop. It puts either a green check mark or a red X in the status bar of your browser as you browse. When there’s a red X, simply click on it to see what errors the validator found. It’s a powerful teaching tool and you’ll soon find yourself obsessed with making sure each page of your site shows the green check mark.
(BTW, I’m far from perfect in this area, but I’m making the effort, and so should you)