I've stayed away from even offering domains. The domain registration business is a terrible way to earn money right now. I'm not saying that it cannot be done, but to be successful you either need a lot of luck or a lot of money. It's too competitive for razor thin profit margins.

As for adding domains on - it has become a gimmick. We thought about it for a while, but the problem is, everyone is doing it. It's not an expected service, but when you can go have control of your domain at a trusted company that advertises on TV compared against the hosting horror stories, it's not worth it for the average client. It really isn't worth it for hosting companies in the end.