SHF & Bird,
The number of pixels does not help in low-light conditions, but adds detail. Digital cameras (most of them anyway) use a technology called CCD (charge coupled detector) to "catch" the light. They act a lot like film, and can "pick up more" if the shutter is open longer. In other words, they work a lot like film in that regard.
So the best way to interpret the specs:
1. Number of pixels contols the amount of detail. 1MP is good enough for a snapshot (3x5), 2MP is good enough of 5x7, and 3MP is good enough for an 8x10. To equal a 35mm film camera they will have to do 8MP. Beyond that, film loses.
2. Check the "speed" of the camera to get an idea of how it will work in low light. Also, get reputable reviews to see comparative specs.
3. Optical zoom is the only zoom you should use. Digital zoom can be done with your photo editor, and is useless on the camera.
I got our Kodak DC4800 last year (3.1MP), and have been very pleased with the results. A 128MB compact flash holds a little over 100 shots at high resolution, and I've taken almost 100 shots on a single battery charge.
I prefer compact flash to smart media, memory sticks and other storage media. It comes in the highest capacities, is the cheapest around, and is non-proprietary. I got my last compact flash at Fry's: $40 for 128MB.