SRB2 Version 2.2.2. is now available. You can find the patch zip on the Downloads page. You will need to extract it to your 2.2.1 folder. It is mostly some bugfixes, and stuff for modders, though there are a few features that I think people will find beneficial.
We have also released an experimental 64-bit build for this. If you intend on using it, you must delete all existing DLL files from your 2.2.1 folder before extracting this patch.
We are still working on getting Linux and Mac updates for 2.2.1 as well as this. There will be an announcement when they are made available.