Yep, I even save two copies of each one of my photos: one I keep in RAW, the other I convert to .tiff or .psd (Photoshop). I convert them because I read that for archiving purposes, the RAW file format is always evolving and/or changing and you can't save it for a very long time.

As an example to this, the first digital camera I owned, the Canon Digital Rebel (EOS 300D) used the .CRW file format for RAW. The camera I now own, the Canon Digital Rebel XT (EOS 350D) uses the .CR2 file format for RAW. These are models that hit the market just 18 to 24 months apart.

As you can see, RAW is constantly on the move as each camera manufacturer tweaks White Balance, sharpness, contrast, noise reduction, etc. in their brand.