This was my first experiment with building a panorama. This is Polychrome Mountain in Denali Park in south-central Alaska.
I used an 85 mm lens on my Canon 20D. Used manual exposure (exposed for highlights) and focus at infinity. I held the camera horizontally (landscape). This was all hand held; the closest points (extreme left and right of the frame) were over 1000' away and most of it was miles away, so any positioning error was minimal. When I optimized with Hugin I had worst case errors of well under 1 pixel -- completely insignificant.
I've done very little post-processing -- just a bit of curve tweaking, some saturation boost, and a light unsharp mask.
In retrospect, I should have used a shorter lens (perhaps 50 mm) and held the camera vertically. The strip is simply too narrow to be very good, although the detail is incredible. I was pressed for time (our tour bus wasn't stopping for very long) and didn't plan out what I wanted to do. My 50 mm lens is plenty sharp itself. Using a monopod would also help, not so much to avoid positioning error (which would be more of an issue with the 50 mm lens since I'd have more foreground) as to ensure each photo was taken from the same vertical angle (to permit me to use as much of the shot as possible).
My other technique of shooting with two focal lengths might also have been helpful, although less so than with my other panorama, which had less foreground detail to begin with (and where that foreground wasn't in focus anyway, and mostly served to frame the image).