vanchi

There's no way to determine if they are primarily tech workers in this group, as they seem to value their anonymity very much. (from their fb page)

Nice UI touch there, Project Noah.

Here's another interesting app: http://leafsnap.com/ Leaf snap, click a photo of a leaf and you get ID suggestions. Both apps are very cool!

Circles would make great sense if we can push some circles into other circles. Close friends into friends and friends into general connections.

I think so. Check this video http://www.youtube.com/watch?v=vnv1Mbj1jKw&feature=relmf... They pull the same people into different circles. (People don't fade out)