Hybrid_Jon, my first piece of advice would be 'relax'; you have a great car that you will enjoy, and as a side benefit, you are and will get great mileage.

I have a 2005 HCH like you; my first tank was a bit over 40, and since then I'm getting 48-50. I do not use any of the special techniques mentioned here by the great hypermilers, but I do tend to drive in a more relaxed fashion, and I tend to stay around the speed limit or a little above. My tires are also inflated to 36psi, which is above the 32psi recommended.

If I drive through town on the freeway at 65 (with cruise control), I get over 50 mpg. Driving in town, it depends on the lights and traffic, but I get between 45-48. I have two friends, whom I helped convince to get 2005 HCH's, who are getting similar, and sometimes better, results.

I'm telling you this just so you know that it is possible to drive reasonably normally and get very good gas mileage.

The last thing I'd say is not to worry too much about the exact mileage you get; you are doing a good thing for yourself and for transportation in general, and that is something that is well worth your investment!