I've been getting a bunch of comment spam lately with .info URLs in them, so in an attempt to block them I added a pretty broad ranging MT Blacklist regexp to block anything that looks like a domain ending in .info. At least that's what I think it looks like it's supposed to do. The regex looks like:
If you get blocked trying to leave a legit comment, fire off an email to me and let me know. The regex will probably need a little tweaking.
BTW, for those of you that aren't regex gurus, there's this fantastic site, Regular Expression Library where you can search their library of user submitted regular expressions, and even test out your own. They also have a bunch of links to other regexp resources out there to use.