this is coming from a northerner (indiana) - i absolutely love Austin - seriously, by far it is the best city in texas (at least the ones i have been to!)
I have been working for the past 2 months in Houston, and every chance I get i head to Austin. The nightlife and live music scene there is amazing - there is so much variety and so much to do. The city is just beautiful - there are tons of lakes and nature sites to do things at. The food is incredible down there, and the people were all so friendly.
After the awesome experience I had in Austin, it is currently top on my list for grad school as well. If you have a chance - get down there - I'm sure you'll fall in love with the city