Joe Schorr, Sr. Product Line Manager of Photo Applications at Apple reassured customers in this thread:
As I'm sure many of you know, it's not Apple's policy to provide a public "ETA" on future releases, so I can't post anything like a timetable for when support for the newest RAW camera formats will become available.
But I can tell you this. We at Apple are ACUTELY aware of the pressing need to get support for the newest round of camera into your hands as soon as possible. This is a top priority. We have members of our own team using these cameras, so you can imagine how interested we are in seeing this support integrated into the Mac OS and our photo applications!
We fully intent to give our customers what they need in this regard.
Sr. Product Line Manager, Photo Applications