Well, that's the crux of the decision really. Digital camera bodies will come and go every 18 months or so, but your lenses you keep through it all. That's why I went with Canon. IMHO, they make the best lenses and have a very broad range of focal lengths from 2.8 and up. My advice to most people who haven't bought into a lens system yet is to go with Canon, start out with an inexpensive middle of the road zoom so that you can figure out what kind of pictures you'll be taking and hence what range of lenses you'll need.

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You have your way. I have my way. As for the right way, the correct way, and the only way, it does not exist.