Thanks for your reply. Indeed, if you look at it from a price point view there isn't much room between the K100D and the K10D. However, in the past Pentax made different cameras available at very similar price points, eg. MZ-3 and MZ-5n or MZ-6 and MZ-7 (IIRC). Those cameras had slightly different specifications and targeted different buyer groups.
Although there isn't much room between the prices of the K10D and K100D, I think there is a niche between the user groups of those cameras. In the analog line up of the past the MZ-5n catered for such a public. It had the compactness of the MZ-6 but was slightly better built. The MZ-5n had more advanced metering than the MZ-6 but lacked the differerent program modes of the MZ-6. At the same time it also lacked some the features that belong in a real pro camera (like weather proofing or high speed motor drive).
I guess it's clear that I liked the MZ-5n form factor very much and I would really love a similar DSLR. Probably I am just wishing for a camera that Pentax will never produce

On the other hand, the K100D Super looks like a very good camera. I will have close look at the specifications again. There is a good chance it's got everyting I need.
Bert
EDIT to add: the price difference in Europe seems to be a bit bigger (prices from a German reseller): K100D Super body only 519 euro, K10D body only 829 euro. I don't know whether there is a rebate program in Europe.