Swanson - 10:59 pm on Feb 7, 2007 (gmt 0)

Flippance aside, I would be interested if anyone has any evidence where non W3C validation has actually resulted in ranking problems.

I ask that as I run 400+ websites - and they suck as regards good markup but they do just fine in ALL search engines.

I don't even have a clue what XHTML is - I have no idea about CSS, or even good HTML. But the sites have good content, good links, good structure and render in all browsers.

Just thought that "cleaning up the web" might be a complete waste of time in that respect - I imagine many sites that "pass" the test look awful, are unuseable and provide no benefit to anyone?