Mike, my conclusion, at the moment, about preserving, to some extent at least, the quality of the original when uploading pictures is this: if you save your picture in JPG quality such that the file you get is much greater than what APUG requires, your picture will be changed by the site and you will lose definition, as far as I can see; try being close to the prescribed parameters. Resharping, after resizing and jpg saving, must be done Very carefully (at least using unsharp mask, as far as I can see), otherwise the picture will look quite ugly!
I share your frustration about uploading fuzzy photos, particularly when you start with a nice sharp picture you want to share with others; was very surprised that my uploaded pictures to this group looked as sharp as I could hope for (after all if fuzzy pictures is what one whats to make, than Hasselblad seems to be the wrong choice of equipment!), haven't been that lucky with other pictures (but I cant really understand why, perhaps the square pictures using all allowed pixels make a difference compared).
If you discover some threads which points to improving the suggested method, please let us know.
//Bertil