It has already been mentioned that the term bitcoin has been in use in the public domain long before the Trademark was filled. I don't think the TM has a leg to stand on. Also, anyone with bitcoin in a domain name should not have to worry about this TM if their name was registered and in use before the TM was created. The person with the TM should not be able to get those names that is known as "reverse domain hijacking".
It would seem that prior use is irrelevant in regards to trademark law. Everybody should reread this post:
http://forum.bitcoin.org/index.php?topic=26527.msg333383#msg333383The users need to plead a case based on the term being generic and also that the bitcoin community represents a "substantial majority of the public." That is what will slow this down.