There is a fine line between easy communication and just plain distraction. Personally, I think that a group of programmers all working at a big circular table as if they were having a family dinner creates a little too much togetherness.

In the vein of scientific research, it has also been shown that Instant Messaging can be a valuable tool for communication and collaboration, because it allows a person to silently indicate their availability for all connected contacts to see. I would recommend a more separated seating arrangement that allows more privacy, and the use of an IM client for easy communication with team members and other co-workers.

The point of Facebook is for users to share information with other users that they designate, not for Facebook to give away any and all users' information for their own benefit. And the way that they justify doing it is just plain sneaky.

Food literally can be social networking! Anyone ever heard of Bakespace.com? It's like MySpace for cooks, allowing members to discuss and share their favorite recipes (along with a host of other features).