I was only addressing the GPLv3 programs because that was the grandparent was addressing. For Yosemite, lot of the other software, with the notable exception of

I was only addressing the GPLv3 programs because that was the grandparent was addressing. For Yosemite, lot of the other software, with the notable exception of Vim, seems to be fairly close in version to what the current release is. OpenSSL is an outlier too, but that may very well be a case of the amount of API changes with OpenSSL 1 that didn't provide a clear benefit, but did create new openings for problems. With Mavericks, the situation is a lot like any other Unix distribution. Unless you have a very good reason for it, you don't want to break working code during a (mostly-)automatic update. For example, RedHat shipped Python 2.6 as the default for many years after Python 2.7 was released -- using 2.7 would have broken user installations. Personally, I'd like to see Apple volunteer with the efforts the BSDs are making to create good BSD-licensed alternatives to the GPL software that's shipped. However, as you briefly mentioned, a lot of the software has different quirks and design decisions that will cause code to break. BSD grep, for example, mostly Just Works, however, I had to switch back to GPL grep on my FreeBSD box because a few bits and pieces had changed enough to make things a hassle.