true notthatugly, but at the same time, if someone has a problem with their theme the first finger pointed is validation and it's a, er, valid point as it lets the user note if there are any missing divs and so on. though when someone tells you your site hasn't validated because of something minor, like one li missing, it's a bit off for me. still, when someone validates has a problem and find they 400+ validation errors and oh god the sidebar keeps going lopsided, has to be a cause for concern.
it IS a geek thing, it is a bit of snobbery as well (ha ha, your site doesn't validate you suck don't you know anyting etc), , but it also has a degree of best practice in it. at the same time i know plenty of popular sites, with mass traffic, a dogs dinner of a design and wouldn't validate this century let alone this year, and yet they still look bloody fine whatever you view it on.