Ever since I downloaded Final Cut Pro X I've been waiting for Canon (or Apple) to come up with a plug-in to import MXF files from my XF105 and XF305.
I went to an Apple press launch of FCP 10.0.3 on the 1st of Feb and they mentioned that it would be launched within the next couple of weeks.
Well, it is now available.
The guy at Apple said that it will take the MXF files and re-wrap them in .mov - no transcoding is required.
Go to...
http://usa.canon.com/cusa/professional/products/professional_cameras/cinema_eos_cameras/eos_c300#DriversAndSoftware
Choose your operating system - which has to be 10.7 (lion) and you'll see the plug-in ready for download.
Although it isn't available for earlier operating systems - buildyo2 (on an Apple forum) has already worked out a workaround.
You can find out how it was done here...
https://discussions.apple.com/thread/3131953?start=180&tstart=0