Up4 (you need to login to Facebook to see it, hello walled garden!) sounds promising! Can't wait for the official blog post :-) on the ActiveState Blog or David Ascher's Blog. Sounds like a great app to discuss at a Vancouver Facebook camp or at BarCamp Vancouver 2007!
FROM Facebook | Up4:
Use Up4 to express when you're open to doing something, and the kinds of activities you're up for. Up for the beach after work? Checking out a show Friday night? Or just hanging out Sunday afternoon?
Use Up4 and others can let you know they're up for it too. Up4 makes it easy to spend more time with your friends.
So... what are you up for?