Man, do I love TacoDeli. I been going there since 1999, right before I went to law school. I avoided it at first, mostly because every cafe/restaurant which had previously been in that location would crash and burn promptly after starting up. I didn't want to get hooked on a doomed taco. Fortunately I was wrong about the location, and once I visited I was instantly hooked. Moreover, thousands of other people are apparently hooked. TacoDeli has won six Austin Chronicle readers' choice awards. It's even quite popular on FourSquare (I'll have to check on GoWalla).
I'm most fond of the steak frontera funditos (pictured above). I also like the Mexico City and the al pastor tacos. Furthermore, the have excellent queso and they stock the fridge with delicious Mexican Coca-Cola (the kind with real cane sugar).
The gf and I ate lunch there today. I was initially concerned about the weather; however, the patio was quite comfortable in the sun and their were plenty of outdoor propane heaters on standby. The only unpleasant aspect to the entire meal was the loud woman who kept describing her last child birth experience in graphic detail (i.e., only an obstetrician would not mind hearing this while eating). It was freaking out me, the gf, and several other diners.
I plan to hit TacoDeli quite often once the weather warms up. Tacos are great before heading into Barton Creek for photos, biking, and other amusing activities.