Why RAW you ask? OK, you didn't, but I'll tell you anyways. The RAW format for digital images is akin to a photographic negative, allowing archiving of an unprocessed image, and giving the artist the maximum amount of control over their image processing.
One of the great advantages is that you have about 2 stops exposure latitude in the RAW image, giving the photographer a bit of room to make up for the limited latitude inherent in the digital format.
As Alan Little argues (link via the Blowhards), "Digital can deal with a similar contrast range to colour slide film. It has nowhere near the range of colour negative film or, especially, black & white film." Which is true, but does not take in to account what can be done to recover detail in both Raw conversion and in Photoshop. Alan also makes the "absolute resolution" argument, which compares the potential megapixel resolution of scanned film vs. digital. But the argument must also take into account the ability of the lens to resolve that much resolution as well as the scan. Digital is indeed behind film in a couple of areas, but they are less extreme than one would think and the gap is shrinking constantly.
All of this, by way of saying that Adobe has upgraded their Camera Raw plug-in to version 2.3, which includes "unofficial" support for the Canon 20D. Also new from Adobe is the DNG Converter, a free software application that allows you to convert RAW files from different camera manufacturers to a Digital Negative Format, which Adobe hopes will become a single standard for archival purposes.
Read more about the DNG Converter and Digital Negative Format here.