For me the question is whether we can say a particular X.0 release is significantly memorable or not, and why (SMP). I think this one will be memorable.
We only do two releases a year. If we did four (which I am NOT suggesting) then I might bump the major version every year and be done with it. But with only two a year a major version bump should be based on something memorable. I'm not a fan of infinite sub-version release numbering. -Matt