I think this thread may be dead, but I had to through in my two cents...
We call seem to be trying to guess the naming convention for OSX based on the conventional naming system that Mac and almost all other software manufactures have used. For example:
FlurbOS 1.0 -First release
FlurbOS 1.01 -Minor revision
FlurbOS 1.2 -Major revision
FlurbOS 2.0 -New release
This makes sense and works well, and thus we are assuming that apple will in some way stick to this naming convention. Unfortunately, the break from standard naming conventions for a marketing ploy is not unprecedented.
Either a: MAJOR version jump or b: MAJOR marketing ploy...
Considering the only drastic change was a new interface, Im guessing b. Microsplats solution for the revision problem in this system seems to be... "We just wont show it" The only way you can find it is by looking at the actual name where you see Win95a, b, c, and so on. Who knows in a few months we may be using MacOS Xb or some such thing. I would hope for X.0.1 but that looks funky two. I also have another opinion on why Mac went with the X. X as in uniX. X as in X Windows. Or even X as in neXt. X is by far the coolest letter, and for those of us who tend to linger in Unix land, it is defiantly attractive.
Back on the topic of revision naming, I think that history has shown when a company chooses to drop numeric version numbers for letters, the revision numbering usually goes on the window. (never saw a Windows NT.1 did ya?). My thought is that apple will either eventually drop the X for 10 or we will never see minor revision numbering again.