He stopped playing there before they banned him. He's more interested in getting the word out and/or having the site fix its broken support practices at this point I think.
It's true that people on your Skype contact list can get your IP address. Skype is a peer to peer service, and so your client needs to be able to directly connect to your contacts in order to talk to them. People can get your IP address in various other ways, such as asking you to visit a website they control. There's no easy way to find someone's IP address if all they do is play poker against you (on a trustworthy site), however.