The bottom line is Money...the more megapixels you want, the more money you have to spend. The prices have really come down quite a bit and quality cameras are more affordable. When I bought my digital, I too wanted a camera that I could afford but would grow with me and not "go out of style" a year later. That is why I chose a "Prosumer" digital camera....A professional consumer model, LOL!! ( My friend who designs for Lillian Vernon, works with a digital camera that costs over $20,000 - Eeeeek! It's the company's camera, not my friends - DROOL!)
I do use my Olympus for graphics designs and I use it for personal use, as well. I probably use it for personal than I do for my company, LOL.
Really, If you want to capture the best quality, I would choose a camera with 4 megapixels CCD or higher for the best resolution. Another thing to remember is If you print your digital pictures on an inkjet printer, you need to make sure that your printer uses archival inks or the photo will not last...over time it will degrade or disappear. These days, the pictures you capture on a quality digital can be output straight to film at a reasonable price. (About the same price you pay to develop film) Very Cool!