texasville - 2:57 pm on Jun 13, 2006 (gmt 0)
In my sector, almost none of the top ones are compliant. Heck, most of them don't even have a doc type. Mine all are compliant on everything I build. But that is for me.
BTW..being compliant won't always catch everything. Even the w3c checker misses stuff. Run xenu linksleuth to be double sure all your links work right.