From:
http://news.com.com/2100-7355_3-5098688.html?tag=st_lh
=================== They have stated that they want to release a new version of OS X every year, but this is the first time they have hinted that they will not be supporting any particular OS X version for more than that year and that they expect all their customers to upgrade their operating system on a yearly basis," he said. ===================
So I guess the difference for Mac OS and Fedora users who want to stay current with security fixes is that the Mac OS guys will have to pay $129 each year.
Of course the Fedora legacy project might remove the need to upgrade your OS each year.
Dax Kelson