I will start a new v5-beta branch soon. I have seen that a number of things have been changed since the last stable release. Most importantly, some of these changes fix bugs. Bug, that are hard to fix in the current stable version. This is because v5 got not so much exposed to reality, but adoption rate seems to increase and so we have been able to iron out some issues while doing refactoring on the latest development release.
I have thought about backporting the bug fixes. However, this doesn't seem to make too much sense: it is a lot of work, and, when done the current v5-stable will have code very close to the development branch. So I decided to accept the bugs for the time being and instead see the we can get a new 4.6.0 stable release as soon as possible. The first step on that route is to create a new beta. Based on past experience, I think we can promote that the stable in September (as we already got some good feedback on it).
Anybody with problems in the current v5-stable should simply update to the beta as soon as it is available.