Checked in Firebug, Chrome, Firefox Webmaster Tools, and via validator. Half indicate stray characters. Half don't.
Often times, you can solve an issue like this with Firefox Web Developer Tool's "View Generated Source" which is important for browsers like Firefox that are intelligent enough to fix the problems themselves (unlike IE I might add) Non breaking spaces are a great example of an element that can toy with IE but will never show up on Firefox with this feature. Here's the link if you don't have it: http://chrispederick.com/work/web-developer/
I'd say take 20 minutes to grep your code again for the string " . " If that doesn't find a result, by all means consider Pat's suggestion. That's one heck of a lot of divs to deal with!