Mac OS X is an excellent operating system, but is there a possibility of a Mac OS XI?! (Why do I always have this ?! when I talk about Mac OS ?!) 
i am sure there is. youll just have to wait for it.
Definitely there will be Mac OS XI and XII And XIII and...........
It seems that Steve Jobs is back with much more enthusiasm and zeal for creation. He really deserves the credit for iTunes success as well as Mac OS X 10.3 Panther's design and stability. It really feels like Unix!
we'll spend ages on 10.4, 10.5 etc till we get to that, and from experience will have to shell out $100 every time....
still, can't wait to see what it will be like
ora
It's Just a dumb misoonderspraken.
XI actually means 10.1
Basically:
XI is supposed to be X.I
I was also wondering bout this wonday when I came across a site. Turns Out the idiot was running 10.1
They just don't realise that XI = 11
When Mac OS 11 is released it will be a signifigant jump from X. Similar to (although probably nto quite as signifigant as) the jump from 9 to X. The way they have been doing it (10.1, 10.2, 10.3 etc.) when they stop calling it 10 it will be something wholly different (and I imagine extremely awesome). Maybe like those old Knowledge Navigator videos they had. I have heard that 11 will be the next releases after 10.4, but even if that is true I wouldn't expect it for atleast a couple of years after Tiger is released. There is absolutely zero info on 11 right now, so if they are workign on it, it is being kept extremely hush hush.
I thought that Mac OS 10.3 Panther was big enough to merit its own primary version number. But with 10.4 looking so cool (and still no new primary version number), it's almost as if Apple is getting bored of its own innovations.... Mac OS XI really must be a kick-A OS.
Panther was awesome, don't get me wrong, Expose is a revolutionary tool, and that alone would have almost made Panther worth the $129. However, Jaguar to Panther was no where near the same magnitude as 9 to 10. When 10 becomes 11 there will be a fundamental change in the way we do things. It will be big, a whole lot bigger than a few extra features (as awesome as those extra features may be).
What about 8-9, though? About the only improvements I saw there was slightly improved USB support and an added Window menu. (I think that Sherlock 2 was a step back, because it launched more slowly.)
Since 10.4 is tiger, 10.5 should be lion, then they could make 10.6 Liger!! That would be funny, at least to me. If you're wondering, Ligers are actually real animals...a mix between a lion and tiger, they are huuuuge...much bigger than either of their lion/tiger parents.
I saw a photoshopped pic on the web of Steve Jobs holding an OS X 10.8 Liger box with the caption "It's pretty much my favorite Operating System."
its my thought that os 11 will be the next big leap in all os platforms. with all the current buzz of physical user interaction, the next major os release will utilize multitouch technology, and a radical graphic redesign best suited for our physical interaction with the computer...
OS X is the system software name. 10.x is the version (you can start version numbers at any point you wish, kinda like check numbers).
Theoretically, the name OS X could never change.
OS X 100000e80.01.99
sweet! 
Try Leopard.
My suggestion is that the jump to 11, XI or whatever, should be when they drop PowerPC support.
Note, my Tiger's uname says 8.10.0.