I too am posting mainly to get email updates of this thread.
That said, this started for me (Seattle eastside) about a month ago and only in the Firefox browser; no looping ads in Chrome where only problem is video timing out without loading . I'll keep track of the ads and time if I encounter it again (but it was so mind-numbing that I'll probably go straight to network when possible if it does happen).
And that said, I'm surprised to learn that folks have been posting about this since beginning of the year (so it doubtelss started long before) and comcast is only now beginning to rectify it?! What do we customers have to do to get your kind attention? I mean seriously, what? Thank you.
Edit: Oops, make that 2012 when posting began. Geesh.