What do you think will be the next name (number) of Mac OS. "OS XI"?

What do you think will be the next name (number) of Mac OS. If the last version Mavericks is 10.9 and the "X" in OS X stands for 10. Will it be OS XI (11)? They can't continue with 10.sth. Because if it was 10.10, it would be like 10.1.

Do you think it will be something with completely new design? Something REVOLUTIONARY?