The DC High Dynamic Rangers Message Board › Great article on how to get sharp images while shooting HDR
The most surprising thing he said was:
"Photomatix is the biggest HDR program out there but also causes the greatest image degradation during the tone mapping process."
Jimmy suggests either Oloneo (which I use) or HDR Efex Pro (my 2nd choice) because they don't soften the pixels.
I've never been a big fan of Photomatix but that is what I started with like everybody else shooting HDR. :)
I think this is especially good information for you guys that shoot Canon. :)
Lots of other great tips in the article so please check it out and these tips aren't exclusive to just HDR images.