Over at the XNA blog they have announced that XNA Game Studio Express version 2.0 has now been released. Full information and links to the download may be found here. Unlike the beta the released version allows PCs and Xbox 360s to communicate over the network. There are other changes and enhancements as well but the XNA team does a much better job of explaining them than I could hope to.
BTW if you are using XNA GSE and have questions you will want to know about the XNA Forums. These forums are THE PLACE to go to when you have questions. I think that if you check them out you will find that a lot of questions have already been answered there. My motto has always been "anyone can learn from their own mistakes; the smart people learn from other people's mistakes." Be a smart person. :-)
Of course if you have already learned a lot you can be an important part of the community by sharing what you know on the forums. Join in and share the knowledge you have gained.