One thing I've noticed living in Austin is that the technical talent pool is still not as deep as the bay area, which isn't surprising but is also true. Austin is catching up and in many of the local tech meetups, I've seen people fly down from the valley and give a talk about their tool/company/technology, which is a promising trend.

As others have mentioned, the cost of living is significantly lower, and I would wager that Austin is a pretty nice place to live as a young person, with its great coffeeshops and bars and live music scene.