We made it out OK. Waiting until Friday morning may have been what helped us. For those familiar with the area, we live in the Southbelt area, about a mile from Beltway 8. We took the beltway to Hwy 90, then took Hwy 71 when we reached the little town of Altair. When we reached Columbus 71 dog-legged and we had to get on I-10 for about a mile. This was a very heart wrenching moment. The sides of the freeway were jammed with stalled vehicles with hundreds of people milling around, many wandering with gas cans in hand. The police had done a good job of clearing the way so that thoseof us with gas could get through. The sight was very surrealistic, and there is no way I can fully describe it here and do it justice.
After we got back on Hwy 71 we were able to move at a steady speed of about 60 mph until we reached Austin. We arrived there with about 1/4 of a tank of gas and were able to refuel and continue on to Llano, about an hour west. Whole trip took about 6 hours (normally takes 5, so we really lucked out).
For those of you still stuck out there, or who couldn't get out, we'll be thinking of you. Hopefully it won't be too bad and you'll ride it out OK.