Latitude by Google

"Google has launched a version of its Latitude-a sort of GPS-powered friend finder-for the iPhone. Unfortunately, it seems it was banished to web app-only ghetto by Apple."

This unfortunately is web-based so it won't take advantage of the "push notification", and initially it will only be available in the U.S., New Zealand, UK, Canada and Australia. It would have been really cool if this could have been part of the Maps app that comes on the iPhone. I tried something similar called Loopt, and really never got much out of it, so I don't think this will appeal to me. Anyone out there excited about this? Or do you use something else?