Originally Posted by rowan

Lenses are the long term investment, the body is disposable. (Ok, so that's a little sensationalist, but technically the body will be obsolete within about 18 months... the lenses will keep you going for years and years.)

If you're doing commercial photography then forget "consumer" grade zoom lenses. Stick with L. I would also recommend avoiding EF-S lenses since you cannot use them on a non 1.6 crop camera. Remember you're investing in lenses... ;)