Yes. I'll crop, sharpen, reduce any noise and tweak the colour balance and exposure in Canon's Digital Photo Professional. Sometimes I'll also do some touch-up (e.g. cloning out stuff I don't want in frame) in Paint Shop Pro.
Yes, and they always have. From the old days where slight variations were made in the dark room to chemical composition and temperature, to filters, to mechanical devices used to create vignetting... to modern post-production methods mentioned already here. If you shoot RAW, you must do editing. There is no in-camera sharpening done to a RAW image. In fact, RAW is 100% geared towards giving you the maximum image information to edit to the best possible picture. Anyone who thinks there's some nobility in printing directly from an image right out of a camera lacks a basic understanding of both film and digital photography.
