Web 2.0? Here's a letter from our Lawyers.
Be careful what you call your conferences, it appears the usage of the term "Web 2.0" is owned by (or rather they think it's owned by) O'Reilly.
A conference in Cork (Ireland) have been asked not to use the term.
http://www.theregister.co.uk/2006/05/26/web_2point0_battle/
Scary.