And that information will not direct you to buy a Nikon. But it should.
Why I Shoot
Lessee here...about six camera generations ago (1.5 human years), I was ready to buy my first DSLR with a little hope of making a business out of it at some point (by the way, that time is now; I quit my job, and I really appreciate your business in supporting my fam.) it's also no secret among those who know me that I'm a bit of a gearhead. Started with hiking boots, moved on to backpacks, then rock climbing, then mountaineering, then mountain bikes, then telemark skiing, the white water rafting, then woodworking, and now it's photography equipment.
It's not that I always get the best gear, it's just that I always know what the best gear is...and how much it costs--in dollars and plasma. I just like knowing about stuff, and the minutiae that make the difference between a quality piece of equipment and a discount brand (it's amazing how often YKK zippers are involved (nickel plated number 8's, to be precise)). And knowing these things often helps me get the most out of the less expensive stuff (like this camera bag I picked up in New York last January--it doesn't have YKK zippers, which also speaks to the quality of the rest of the bag, so I know I need to treat it with a little more care; and that $50 has lasted longer than if I hadn't known).
Naturally, I learned all I could about the available cameras so I could maximize my investment. Fortunately for me, my older brother already had a DSLR, and the only better than getting new gear for yourself is getting other family members hooked on the same thing. It's a kind of bonding. And hes the one who invented gearhounding in my family (he'll probably correct me on the preferred size of YKK zippers). Anyway, he had already found most of the important details and was all too happy to help me shop.
The first major question in this sort of endeavor is which brand to buy. With cars, you may ask yourself, "Import or domestic, Kia or Geo, Ford or Chevy, Honda or Toyota, BMW or Mercedes?" in cameras, there's really only one choice, and you can hate me, but it's true: Canon or Nikon. The good news is, it's like deciding between Mercedes and BMW, but the price is the same as the Chevy!
Here's why you should only consider the Canons and Nikons: 98.53% of all photographers use one of these two, and they always have. That means all you have to do is type "N" into the google search bar and it immediately auto fills with "Nikon" and a bajillion and a half websites with Nikon information.
It also means that there are loads of lenses and support equipment for the two biggest brands in the universe. Oh, and il admit it right here: Canon is by far the bigger company. So, don't mess around with other brands because you're limited in the after market gear you can get, and the amount of info available from other shooters, including Sony. I mean, Jaguars are nice and all, but good luck finding parts and a mechanic.
Nope, stick with the big two.
Now, the definitive information for which brand to buy, as told to me by my brother. Buy the one your friends have. This way, you have a ready source of info on settings and accessories from someone who already speaks the language (yeah, it's a whole other language). So, with a little nudging from said brother (who owned a Nikon, and may have been interested in whatever lenses I might buy) I also bought a Nikon. Now, it was no small decision for me because while my bro shoots Nikon, my Dad shoots Canon. Obviously, things were a little dicey for a while. They say the Civil War put brother against brother and father against son; but that was nothing compared to a houses divided by brands.
So, I employed the second definitive choice making tool: I picked them both up and held them in. my hand. And that was it: Nikon. Canons are clunky, and poke me funny, and the on/off switch doesn't work with one hand, and WHAT IS UP WITH HAVING TO TURN IT PAST ON TO ENABLE APERTURE CHANGES IN MANUAL MODE? I read somewhere that Nikons were designed by Ferdinand Porsche, and anyone who designed the 944 certainly knows what he's doing, and it shows in Nikon bodies. They feel good, and the buttons are all in the right places.
My D90 body arrived from J&R photo five business days later. I only bought the body because lenses are such a good deal used on KSL.com, and new lenses lose a certain amount of value once you drive them off the lot, whereas used lenses remain the same price, or appreciate over time.
And that was it. I started shooting daily, and studying, and trying out different lenses and cameras. I've now owned (and sold) five different Nikons and three different professional Canons and an arsenal of lenses for both, name brand and third party. And I'm still a Nikon guy. In fact, I bought a Canon 7D (flagship of their lineup, $1500) so that I could learn to speak Canon for my students. I sold it last week, convinced that it's not as good in almost all respects as a D90 ($749).
Having said all that, it's totally the photographer that's makes the pictures, and not the camera. A nice camera doesn't make better pictures anymore than a Steinway makes good music. I sound just as bad on a Steinway as I do on a Fischer Price (and no matter how much I blame it on the Fischer Price, you and I both know it's me). Nevertheless, there comes a time when you outgrow your tools.
My recommendations, then, if you are thinking about buying a camera.
If you have $300 and want to occasionally make some decent pictures at the instant you press the shutter button: D40 with whatever lens you can find it with (this is used or refurbished only). Great camera.
If you have less than $600 and will often take pictures, and may even consider making some money: D3000, D5000, D3100, and maybe even a used D90, in order of cost and preference.
If you have less than $1000 and want to not be held back by your camera and have the flexibility of buying older lenses for less expense and have a camera that can give you a start professionally: D90 (yes, even better than a D300(s)).
If you have $1200 or are looking to upgrade from any other camera: D7000. This the best value on the planet, amongst any brand.
That's my soapbox, and my Nikon Philosophy. I can't believe you read this far! Go make some pictures.