No Penalties for Invalid Markup
You may have spent countless hours making sure each and every one of your pages had valid markup, or spent a few hundred (or thousands) making sure your designer abided by the W3C standards for valid markup. Well it turns out (you may have already had a good idea) that invalid markup (poorly formed documents) really may not be a factor in securing high rankings on the search results pages.
On a blog post about "fuzz testing" of all things, Google's Matt Cutt mentioned that:
At a search engine, you have to write your code to process all that randomness and return the best documents. By the way, that's why we don't penalize sites if they have syntax errors or don't validate - sometimes the best document isn't well-formed or has a syntax error.
We've written a lot about Web standards in the past here at Website Magazine and still believe that well-formed pages benefit everyone - not just users but search engines too. While it's refreshing to hear that Google (and I think it's safe to assume other search engines as well) don't penalize for poorly formed pages, it's even better to hear that the information and not the coding is what's most important.