This site at the moment is XHTML 1.0 Valid. The only exceptions being a few odd tags in old posts that have not been edited yet.
What does this mean??
Well it means that the site follows the guidelines for code layout and SHOULD display the same in all browsers. However this is not so as no browser implements code in the same was as another. So while it looks ok in IE6 it sucks in Mozilla and Firebird.
But as 90% of the world uses IE this is good enough for the time being until i get it all fully cross browser compliant.