Surprisingly, at least to me, we managed to make 3.1.0 release exactly as planned, i.e. today, without any delays. The price for this is that there are a couple of known problems in this release (see the errata on the release page), but we decided that it was not worth delaying the release for them.
This is not the most exciting release in wxWidgets project history, but it's still very much worth upgrading to as there has been a huge number of bug fixes in it, especially in wxGTK3 and wxOSX ports. Of course, as usual, there are a few new features as well, see the web site for a brief list and the change log for a fuller one and I'll try to find some time to write in more details about one of them, wxNativeWindow here in the near future.
The next goal is to release 3.0.3 to make at least some of the bug fixes, if not the new features, from 3.1.0 available to people using the system packages under Linux or just too cautious to start using the "development" releases (even although in my opinion this is not really justified as, on average, 3.1 branch has fewer, not more, bugs than 3.0.x one). As for 3.1.1, this will depend on how quickly the changes accumulate in the master, we'll see how it goes. In the meanwhile, we hope that you'll enjoy the new release!