If you are storing user details such as location, username, messages sent between users etc do you need to register this information with the data protection act?
Not that I'm aware of, though it looks like a UK law and I'm in the US. Here's the the info on the Data Protection Act. I would think the info you want is in there somewhere.
You may want to look in to whether or not you are legally bound to disclose what information you are collecting to your users, a la a terms of service page or privacy policy.
