Don't make the same mistake I did. I have a Canon 5DMK2 and I wanted something decent to make edits to my pictures when I'm on the road with my MBP, and I was suckered in by the $79 price point for Aperture. I downloaded a trial of LR and had fantastic success with it, but I didn't want to spend the money on it since Aperture was so much less. Huge mistake. LR3 is easily 10 times as fast when editing large RAW files. Fair warning to anyone out there considering Aperture for the same use.