Apple recently posted some updates to allow support of RAW (.NEF) files from some newer models cameras. From their Read Me:
This update improves RAW file format compatibility for the following digital SLR cameras:They also addressed some other RAW issues with the update, which is available in both PowerPC and Universal versions.
-Canon Digital Rebel XTi / 400D / Kiss X Digital
-Nikon D80
-Pentax *ist DS
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