I had the same problem a couple of days ago. Telltale's site wouldn't load no matter what I did on my PC.
But then I actually managed to get it working by going into my router's config and switching from British Telecom's DNS server to Google's.
Then this morning it was down using the Google DNS as well. But now it's up again. o_O
Do you guys have some sort of rouge DNS record flying around or something?
In my spare time I'm filming video reviews about Comic Books and Manga. If either interest you, would you mind giving my site a look at commanga.com