I just got the latest version of Aperture and all I can say is WOW. I didn't think Apple could improve the RAW convertor but they managed to.
There a new interface which is vastly improved and they added plugin architecture so 3rd party developers can port all their PS plugins (like noise ninja) over to work with Aperture. This program will end up with a lot more photoshop like functionality in the future.
At $200 I believe it's cheaper then Lightroom as well.
http://www.apple.com/aperture/
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