If it weren’t for the SXSW conference in 2007, Twitter may not be the household name it is today. But two years later, how did Twitter hold up to all the hype? Is Twitter still the reigning champion of SXSW or is there room for another conference poster child?

I was at the SXSW conference both last year and this year. While I missed the initial swelling of fans that Twitter gained at the conference in 2007, I was already a member of Twitter and watched in wonder as the service grew in popularity and began to realize its potential. I witnessed the rapid uptake of Twitter’s APIs from the developer community, and the subsequent output of relevant applications that gave Twitter its value on a fruitfully adorned silver platter.

In 2008 the SXSW attendees seemed to know the drill: Twitter everything that’s going on at the conference and you’ll eventually find yourself in the tangible presence of others like you. From passively stalking partygoers to merely meeting up with old friends, Twitter was an established necessity for navigating the thousands of fellow nerds that had flocked to Austin for SXSW.

So what about this year? As a reporter of social media-related news, I found myself looking for the next SXSW success story. Every fledgling startup that finds itself at SXSW is well aware of the possibilities that such a large group of early adopters can offer. And before the conference even began there was buzz of many location-based services that could be the next big thing to emerge from SXSW. In that category we saw services like Foursquare and Whrrl 2.0 emerge as location-based mobile applications essentially looking to take the Twitter concept to the next level.

I’d agree that location-based features will eventually be usefully integrated into Twitter itself, so it was great to see the excitement of new mobile services that could in fact be the next big thing. But location-based mobile tools aren’t new. This leaves the problem of execution to the new services. I particularly like Whrrl 2.0 for its social capabilities and the URLs provided for multiple users to contribute to a single event or story. What remains to be seen, however, is if the location-based mobile tools will be most useful for large events such as SXSW, or if their value can carry over into broader use cases.

In the end I would say that Twitter still managed to hold its own. I personally found myself using Twitter to connect with old friends whose numbers I’d misplaced in the past few months, or meeting people in person that I’d been following for some time. Twitter’s biggest success, however, may be the way in which it has allowed those unable to attend SXSW to still take part in the conversations going on at the conference.

Another way in which Twitter has helped expand SXSW is through its platform, which has catapulted third party developers into success stories on their own. We saw a number of Twitter applications being promoted and utilized at SXSW, so in a way we’re seeing the Twitter legacy live on. May the symbiotic relationship between Twitter and SXSW live on for many years to come.