I forgot to mention... The local TV news spot mentioned that the Hilton was offering reduced rates through sometime in Feb or March. Worth looking into.
Also, there's a review on Trip Advisor, from what sounds like some Texas State U (aka Southwest Texas St U) students...
Austin: Hilton Austin Convention Center: "Hilton was top notch"
Date: January 10, 2004
Reviewer: A TripAdvisor User, San Marcos, Texas
The brand new Hilton downtown is incredible. We stayed in a corner room and had a great view of the city. Rooms (especially corner rooms) are huge. Ammenities were outstanding. Beds were awesome. I highly recommend this hotel to anyone. My friends and I were in town to party downtown and the lady at the front desk put us in a corner room away from everyone else so noise was not an issue. At one point we probably had 15 people visiting and there was plenty of room to move about. We loved our stay so much that we already booked 4 more nights over the next 2 months. The location is perfect for 6th street or the warehouse district nightlife.
I would add that if going to/returning from 6th st from the hotel, it would be worthwhile to hop on a bike taxi. I think the hotel is around 2nd or 3rd street, on the easternmost side of where 6th st begins. To get where the action is would take a little bit of a walk, if you wanted to get to, say, the Driskill. Particularly if you're coming back to the hotel after a big night in the entertainment district, this would be efficient and comfortable. The bike taxi folks work for tips, so compensation is up to you. You just flag one down if you see it and hop on.