I really don't care about the numbering scheme and this is irrelevant to the topic of this discussion. We are discussing the PROCESS of development. How the releases are tagged is completely beside the point and could be named after sweet delights, cat names, Parks or even digits of PI. I really don't care and it really is _not important_.
I agree that the numbering scheme should be chosen after the process is defined and not before, and numbering schemes are meaningless (like firefox's) _unless_ they represent some guarantee that the developer is willing to make. In that case the can be very effective imho (see http://semver.org/ for an example).
So if the process chosen makes guarantees about the project, those should be expressed by the version number. For example ubuntu's Server LTS guarantees 5 years of support, and the numbering scheme is year.month, so you know right away that ubuntu 8.04 is still supported right now. They could have named it Ubuntu Pluto and you could have looked up the end date for the support, but since you have to differentiate your releases anyway, you might as well use meaningful numbers.
