It seems that the Where 2.0 Conference is full of pleasant surprises. Today, Yahoo announced its Placemaker platform, and Google also announced the release of their Maps Data API (our Maps Data API Profile) as the newest Google Data API.
PubSubHubbub. Say that three times fast. If you're not familiar with PubSubHubbub, it's an extension of the RSS and Atom protocol that allows the feed to push content out when it's updated. That's just the sort of technology we should see from check-in APIs like Foursquare and Gowalla.