I live in Austin, and bought my HCH in April. It had 4 miles on the ODO when I drove it off the lot. I've logged all my tanks for 'dopmobile' in the Compare section here, where you'll see my first tank at 45mpg. Soon thereafter I began achieving 50mpg+ tanks.

Even with the A/C on, I can manage 49-50 mpg, as long as I keep the Econ button on. At stoplights, switch the fan off of Auto and activate the recirculate button. When the light turns green, turn it back to Auto and deactivate the recirc button.

Recently, I changed my 5-mile commute from an all-highway route to an all-surface street route. It takes me twice as long, but despite the occasional red light, I've managed to raise my average to ~60mpg by driving very conservatively and using a method similar to the "pulse and glide" method popularized by the recent PriusII marathon.

From my experience, even with a brand-new HCH, you can achieve way better than the low 30's... you just have to modify your driving habits.