I've spent a fair amount of time in Austin over the last few years. It is a great city if you are young. There is fantastic nightlife, great food, and lots to do in the area. Jobs are plentiful as well with a booming tech industry.
On the downside, it is one of the fastest growing cities in the US, meaning traffic is insane, and real estate prices are pushing way beyond affordable for those looking to purchase their first home.
WRT to the topic, given it's proximity to Houston, I don't think MLB would allow the Rays to move there.