In general, I believe, we should have three releases per year aligned with the Eclipse Simultaneous release: June - SR0, September - SR1 and February - SR2. Whether each release is "feature" or "maintenance" depends on the changes done in this release.Â
So, if we apply the above, for Luna SR1 we are having the 3.3.1 maintenance release.
As Michal started working on PHP 5.6 support and it will be ready by Luna SR2, then we may ship a 3.4 feature release for Luna SR2 and Mars M5.Â
For the official Mars release we can ship either 3.4.1 and 3.5 depending on what's done by then. But it is too early to predict it at the moment.
This way we ship faster new features to users and avoid having unnecessary spitting of code streams. This is actually the approach of the EGit project, it's not anything I am inventing right now :-)