As spllbnd2 said, Sony is more of an entry level DSLR, newer to the market, and not yet had time to prove itself. When I was shopping for my first DSLR, I looked at the Sony Alpha line. They differ from most other DSLRs, in that they offer Image Stabilization, or Vibration Reduction, through the body of the camera. This is an advantage, in some ways. Other DSLRs offer IS or VR lenses, at a higher price. However, with IS or VR in the lens, it's much more effective than in the body. So, a Canon, with an IS lens, or a Nikon, with a VR lens, is going to offer much better results than a Sony.
Canon and Nikon have also been making lenses much longer than Sony, even though Sony took over Minolta. Canon and Nikon have had much more experience making lenses that are more compatible with the digital world. Lenses are as important, if not more so, than the body.
I passed on the Sony and had narrowed it down to Canon or Nikon, when I found a great deal on a used Canon, on Craigslist.
Also, as mentioned, dpreview. They're an awesome site for getting honest camera equipment reviews. Another good one is
http://www.fredmiranda.com/
