Almost two years ago I graduated from iPhoto to Aperture for managing my photography collection. There were too many files for iPhoto to cope reasonably, and I felt I needed more flexibility and power to post-process. When Aperture 3 was released, I duly gamma-tested and then upgraded, and apart from its ability to crash more often than Aperture 2 I would say that the upgrade has definitely been worth it.
Note that you'll have to apply vignetting to your entire picture and remove it as appropriate; and you'll have to remove blurring and paint it in as required.
