Also wanted to help out the people over at Meetro. Here's the low down:
Meetro has now launched its Mac private alpha and is looking for people to participate. We plan on distributing it to the first few hundred people that email us at firstname.lastname@example.org So reserve your spot now! Also, please include the city/state you reside in as well when contacting us.
Meetro is a location-aware IM client, compatible with the major protocols. I can't say much more since I haven't installed the alpha yet.