While kind of big brotherish, it is a cool technology. For a bunch of technology geeks, it is lots of fun, although I think it is really a technology in search of something real for it to do.
You can "beam" your business card to somebody else, although it takes two or three times as long to do it as to assume the position and hand them one. It has a simple agenda, but doesn't let you drill down to find out WHEN the specific talk you want to go to is, or where. It also weighs a half pound, so we're all running around looking like hunchbacks.