Apple has just released an update for Digital Camera Raw Compatability version 2.3 for download.  You can get this via software update or the Apple download page.  The update shows the following:

 

This update extends RAW file compatibility for Aperture 2 and iPhoto ’08 for the following cameras:

Canon EOS 50D
Nikon D90
Sony DSLR-A900
Nikon Coolpix P6000
It also addresses issues related to specific cameras and overall stability.

 

[Download]