WAYN - Where Are You Now? is a campy, simplified Plazes made for the AOL generation. They have done some nice things like included AIM, MSN, Outlook, Yahoo integration for contacts (beware! WAYN will contact those people in your contacts that are not currently members), and has a built-in chat client with location abilities.
All these location services popping up. Seems like a new kind of IM 'war', where your friends are on one service and you are on another service. There will have to be Adium/GAIM/Trillian clients in which you can upload your location/travels once to all of the services.