This year, much of the talk in the hallways and in the closed-door sessions concerns two things: social media and geolocation--usually as a blend of the two.

There's a pervasive interest in the geolocation moves of big players like and , which are now building huge databases that associate location data with places in the real world (indoors and out) using GPS, 3G and Wi-Fi networks.

, which has just announced the addition of a location tag to tweets, is also getting a lot of attention this year. Location tags will eventually contain a name (i.e. 45 Jones Ave.), a photograph of the place, and the actual latitudinal/longitudinal location data.

The huge challenge for newer, younger companies like is figuring out how to access and use those large databases for the benefit of their users. If an API-based approach to accessing the geolocation databases emerges for smaller social media companies to leverage, it would have the potential to fire off the next big wave of innovation in mobile Web apps.

I met a young HP employee here named Max, who wants to build a social-awareness and philanthropy site based on geolocation. In his conception, if Hurricane Katrina happened today, his site could be used to mobilize thousands of people in the area to provide all kinds of aid to the victims. Such a service might enable people to quickly develop ad hoc social networks based on their proximity to the need and their stated interest in helping, should the need occur.