Man-Thing said:
what are some suggestioned features on a digital SLR you would suggest to someone who has never owned an SLR before?
What lenses would be best for lets say a Nascar race? What about filters? I also intend to take a lot of nature photos with people in them.
The first thing I look for in a digital camera once I've decided on a price range, is image quality. The review sites I mentioned above offer a lot of good comparisons of the various choices that are available and offer sample shots and an analysis of the camera's performance where it comes to image quality, color reproduction and granularity. Some cameras don't produce true-to-life colors very well, and other do it fantastically. And, some have more granularity in their shots than others. I've found that the megapixel count usually has very little to do with the image quality for the most part. Once you get above 5 megapixels or so, it really starts coming down to the technology in the camera.
The second thing I look at is shutter speed. dSLR's aren't as fast as a regular film SLR, for the most part, so paying attention to how quickly the shutter can open and close (or, how slowly it can do so if you're doing time lapse photography) is important. Particularly if you're going to be doing any sort of action shots. If it opens too slowly, you wind up with a lot of motion trails and blur when taking pictures of something moving (such as NASCAR racers). This category also includes wait time when you press the button to take a picture. How much delay is there? I prefer as little as possible. And, how long does it take the camera to be ready to take another shot? Can it take multiple shots in a "burst" mode or not? If you're taking any action shots at all, you'll want one that can take a lot of sequential shots in one run without pausing.
Next, I look at low light performance. I like to do a lot of night shots of cityscapes where there is a lot of odd light exposure. Digital cameras are notorious for having trouble capturing low light shots with clarity. They typically add a lot of blur and extra motion trails (particularly if you're not using a tripod) that you won't normally get with a standard SLR. This is another place the review sites usually offer up some good insight.
Another thing I will look at is the aperature settings. How customizable are they? If you have experience with aperature settings on a standard SLR and like being able to tweak them, chances are you'll want them on your dSLR as well. Or, if you're still learning how to use them, they'll give you something to grow into. I like a nice mix of being able to tweak when I want, but also pull from a selection of presets (panoramic, portrait, macro, etc.) so that I can just make a quick adjustment and then get the shot I want.
Most of the dSLR's at the pro-sumer level offer different lense options. My Canon G5, for example, offers some lense options of it's own as well as an adapter option for the barrell that will let me mount compatible 35mm lenses from other manufacturers. Some manufacturers will only allow you to use lenses they market specifically for their camera. Others don't offer any lens options other than what the camera comes with. At the base, you'll want a camera that has a decent built in optical zoom. Most companies compliment these with a good digital zoom addition as well, so you can get some pretty amazing shots once you learn how to use the digital zoom in conjunction with the optical zoom. As a rule, though, the higher the optical zoom to begin with, usually the better. Of course, for some REALLY high quality zoom shots, you'll want a good optical zoom lens that's made for that kind of photography. A wide-angle or fisheye lens can be a nice addition to your camera bag for nature shots, panoramics, or any kind of photography where you'd like to capture more than a standard lens will. As far as filters go, I don't muck with them much with a dSLR. The beauty of shooting all digital is that you can do whatever filter work you want to in post-production on your computer after you pull the images off your camera.
File format is one of the other things I look at in a camera. Is it a proprietary file format or a standard one? I prefer to shoot in TIF or RAW because they produce the highest quality images with the fewest artifacts and little to no clarity loss when you start tweaking them in Photoshop or whatever program you're using in post-production. However, they also require a lot of available memory, so invest in some additional memory for your camera because the vast majority of the digital cameras out there come with a bare minimum of available memory and you'll fill it up fast if you're shooting at your camera's highest quality.
Another thing too look at is ease of use, particularly where the on-screen menu's are concerned. Being able to easily navigate it and make whatever setting adjustments you want to get to, easily and quickly is important. If it's confusing, you wind up missing shots while mucking with the settings. Or, worse, you get confused about the menus and wind up deleting every shot on your camera (I have done this before and boy will it piss you off. Thankfully, there are some utilities out there to rescue images off of a camera disk if they've been acidentally deleted).
A boot mount for an external flash or other accessory can be a good thing to have on a dSLR as well.
And, finally, comfort. How does it feel in your hand. Do the buttons feel logical where they are at for you? Is it too heavy? Is it too big or too small? How would you feel about lugging it around with you?
That's about all I can think of off the top of my head. Maybe I'll think of some more once I've had some more coffee.

Let me know if I can answer any other questions. I'm by no means an expert where photography and dSLR's are concerned, but I've got a little bit of experience.
jag