Something is very wacky at Apple.

The other software update which popped up yesterday is:

Digital Camera RAW Compatibility Update 3.12
This update adds RAW image compatibility to Aperture 3 and iPhoto '11.
• Canon EOS 5D Mark III
April 05, 2012 - 8 MB

But it too points to a previous update:

http://support.apple.com/kb/DL1513

Digital Camera RAW Compatibility Update 3.11
This update adds RAW image compatibility for the following camera to Aperture 3 and iPhoto '11
• Nikon D800
March 22, 2012 - 7.50 MB

Somebody ain't looking after the shop. And it's way too late for an April Fool's Day prank.