What are should I look for in a digital SLR camera?

Image quality: Not that important. All DSLR's -- even oldies like the Nikon D100 and Canon D30 -- will give you great image quality up to 11X14 print size. There may be differences in colour rendition, saturation, white balance and other parameters, but you can generally tune your camera to get what you want. In this department there are really no bad choices.

Metering accuracy: Nikon's metering is generally regarded as the best there is, but there are plenty of people who would dispute that. I'd say all brands are pretty amazing.

User friendliness: Here is something to carefully consider. DSLRs offer tons of controls, but how easy are they to operate? Are there buttons on the outside of the camera or do you have to scroll through a bunch of menus?

Size: A fairly big deal. Cameras are getting smaller and smaller, and some have gone too far. For example, in my humble opinion, Canon's Rebel XT is too small for adult hands. You simply can't hold the thing properly if you are over 7 years old. Try a bunch of cameras and decide for yourself.

Lens selection: Another biggie. Nikon has 40-plus lenses which will work with its DSLRs, including gems from the 1980's which you can pick up dirt cheap. With other brands you may have less choice, and the choices you do have may be very expensive.

Battery life: Not that important. If you buy a current model camera the battery life will be phenomenal. You will only run into power issues if you use the camera in professional applications such as shooting 1100 images in an afternoon. (Even then, I did that with a Nikon D50 on one battery charge.)

Body quality: Again, don't worry about it. Unless you're covering the war in Afghanistan, any current model will be strong enough and sufficiently weather sealed for your purposes.

Image stabilization, automatic sensor dust removal and other gimmicks: Nice, but not deciding factors.

Hope this helps. Good luck in your camera hunt!

A good starting point would be the epinions.com website for SLR cameras, shown below. It'll let you read a number of good reviews, and get stats on each camera listed. Hope this helps.

Check reviews in PC World, Popular Photography etc. Some things I'd check:
1. Picture quality, not only resolution in pixels, but sharpness with the standard lens, color rendition (white balance), noise in low-light conditions, JPG compression quality...
2. Ruggedness.
3. Ease of use [E.G. Are menus nested too deeply? Controls large enough?]
4. Other factors, such as battery life, shutter delay, lens interchangeability, manufacturer's reliability...