I justed wanted to give a quick plug for Smooth. Everyone here knows he gives away great free advice and instruction, but if you are looking to really improve your pano photography, and you just can't seem to get there on your own, I highly recommend receiving some one on one instruction from Smooth.
I've been shooting pano's for real estate the last 7 years, and my process has improved over time, but with just a couple of hours of personal instruction from Smooth, I believe my image stitching process is going to dramatically improve. I'm already getting much better resutlts and look forward to producing much higher quality images.
If you've been thinking about working with Smooth, one on one, but not sure if it would benefit you, I can highly recommend his tuition. You won't be sorry.