The reason and merrit to doing the work in HEAD was: 5.2 was not out there when we started, so we should have worked on 5.1, which was impossible due to dependencies on 5.2 core. So we decided to go with HEAD, also because HEAD usually is a branch where things are expected to break (and we did a lot of changes).
Merging contacts and AMS into 5.2 is easy, same goes for tasks and mail-tracking. What is going to be tricky though is merging Project Manager as Janine did a whole lot of work, especially for Oracle, and I do not want her to have to go through the pain again in short time to update the PM package for Oracle yet again once we merged it to 5.2. Not to mention that the merge most likely will be a challenge in the first place, which should be done, but where we don't have the time for at the moment (though anyone with a little bit of spare time is highly encourage to do this).
