So I had a small hacking problem and the server was used to send several thousand spam messages. As a result, there are several e-mail servers that are no longer accepting e-mail from silverinsanity.com. This means that if your forum address is on this list, you won't be getting PM notifications, forum subscriptions, etc.
Most importantly, this affects new user registration. If you're trying to register and aren't getting the registration e-mail, send me an e-mail (my username @ this server) or IM or tweet or something. I'm benabik pretty much everywhere.
If you're having problems with another domain, post on here and I'll add it to the list. Hopefully this will all be cleared up soon, but's it's pretty much out of my hands now.