As of today, BioWare will be shutting down the BioWare Social Network, or BSN for short, on August 26th. It will be in read-only mode until October 25th. BSN is known for a lot of things, such as being a fan community with some esoteric elements, like people finding out what Tali's sweat smells like (no, I'm not making it up). While most fans met with each other there, some are disappointed with the closure while others are content or pleased with the news.
If you're wondering how much of a cesspool BSN is, you can check out Something Awful's article on it.
EDIT: Corrected and added link to the blog post. Thanks, Elseweyr!