I can't seem to find an overview of all of them, but here are the ones Blackboard said they wouldn't enforce against pure open source software. http://www.blackboard.com/patent/FAQ_013107.htm
I think we have reached the point in the patent wars where nobody cares what the actual patents are. Whenever I hear that a patent has been invalidated, I just reflexively smile.
This is surely an irrational overreaction, but it's not as if the patent system hasn't been asking for it. If the patent bar wants me to bother reading the things they need to clean out the spam, the trolls, and the nonsense.
Desire2Learn is the company that's been fighting to have Blackboard's patents invalidated, and they are maintaining a list of all legal documents pertaining to the case here: