There, the (most) stable releases are always of the form
"X.X.<maximum>" i.e. if you go to gcc 3.4 you will find gcc 3.4.6
(i.e. has bugs fixed)
And the instable one is the one with the highest available numbers.
gcc is probably not a good comparison as it's not a library, perhaps glibc is. However, they essentially do the same thing as us, only with major version numbers not minor ones. Speaking of glibc though, here's an interesting mail from the maintainer:
And one thing makes me wonder a little: why is it still a 0.15
release? After so many years of work.
From a marketing view this looks like an instable experiment and not
as something that can be used in daily work.
I'd like to see that as well.