Uneek makes some excellent points. I also agree about the Canon P&S cameras.
I would start with one of the mid level cameras. The reason for this? The controls on the mid level and pro cameras are similar and more simple to use. The smaller, entry level cameras have less room for the controls, and they try to make each button do more than one task. This can be very frustrating when trying to learn photography, and your camera is not user friendly.
DSLR technology is always on the move, and in 6-12 months, there will always be a new camera on the market. Suddenly folks feel like they are missing out on the ability to take photographs. It's BS. If your camera did what you wanted for the last 6 months, it will continue to work for you. So; as you step into the DSLR market, buy a used camera (someone else wants to keep up with the latest equipment).
Nikon: D80 or D200
Canon: 30D or 40D (after the 50D is released).
Camera bodies come and go; but the good lenses will continue to serve you all along the way. Here again, buy used. With the latest vibration control lenses coming out, people are trading in their non-stabilized lenses. Buy the professional lenses, and stay away from the "kit" lenses. Most kit lenses are junk. There are "Pro kits" that are packaged with the best lenses.
24-70mm f2.8 & 70-200mm f2.8 are usually professional quality lenses. At this level, buy the Nikon or Canon lenses. These lenses are expensive new; so buy them used.
Both Canon & Nikon now have a decent all around lens. Something like a stabilized 18-200mm. These are not great lenses; but they are decent lenses. They have drawbacks; but they also provide some benefits for daytime shooting.
I shoot a Canon 1D MkII. My wife shoots a Nikon D200. If I were to start over, with no gear; I would buy Nikon. This is because the professional bodies (D1X, D2X, etc) are easier to use. The viewfinder is larger, the menus are more simple to use, etc. I also like the D200,300,700 cameras, as they are weather sealed. The Canon's are not sealed, until you get to the 1D series. This makes the most difference in a dusty environment. Not as much of a problem in the rain. A few sprinkles won't hurt a camera; but dust can be a horrible problem.
P&S choice would be the Canon G9 or G10.
I hope this helps.
