[Krofh]

Originally Posted by powerful_rogue

If you send a message from VBMS to a Hotmail account, it dosent get delivered. You can send from hotmail to VBMS and oher numerous email providers and it works fine.

This is because Hotmail has a whitelist-only spam filter. Instead of just filtering out emails from blacklisted domains, they have a tendency to only allow emails from whitelisted domains.
I wrote a plugin for a friend's site awhile back that would fetch your MSN Messenger contacts and invite them all to the forum... unfortunately this was the biggest obstacle, and what we discovered after about three solid weeks of looking into it that is that they wanted us to pay a rather significant amount of money to be whitelisted. On the other hand, I'm affiliated with other sites that don't pay, but I think in those cases there are thousands of users clicking the "not spam" notifications on the emails.
Not sure completely if I'm all right on this information, but either way my experience with trying to get emails to Hotmail/MSN was pretty shitty. I recommend an Internet-wide boycott.