The PhysicsOverflow software is a heavy fork of Question2Answer, a free and open-source software for discussion forums. The point at which the PhysicsOverflow software diverged from the Q2A software is at Q2A v1.6.2. The latest stable build of Question2Answer happens to be at 1.6.3.
Even before the implementation of the hierarchial category system, PolarKernel had estimated that updating the Q2A software would take a week. But I suppose, that after the implementation of the hierarchial category system, an update (which includes re-implementing all the new changes in PO and debugging) would take maybe even months (?). In fact, the new code PolarKernel has written for PhysicsOverflow is more than half the size of the entire standard Q2A.
So I think, that instead of updating our software, which could by very time-consuming, we should list down the features that are present in the newer versions which would be useful for PhysicsOverflow. In general, they would logically take lower priority than the public beta feature requests. So please have a look at the Q2A version history (only the versions beyond 1.6.2 count) and write in the answers if you think any of the features are worth having. Note that some of them, such as the "Stop sending out passwords in registration emails" are already implemented.
The current list
- Combined sub-navigation for user profile and account/favorites pages.
- Maximum rate of wall posts and private messages (to prevent spam)
- yellow-square-beside-username notification for wall post. As discussed here.