While Team SGK is in some senses a very controversial part of the PS3 scene in particular, they have still managed to continue their work in stride with the release of this supposedly 4.31 custom firmware that adds a whole bunch of features that are worth talking about. In many ways what this firmware does is attempt to squeeze in all of the latest updates from other projects like Rebug and Multiman to create something that can be used in just about every scenario. Some have called their work copy-catting, but this is still an important scene release nonetheless.
As usual, the translation is going to be really rough here, so you may want to consult the source or this video for more info. Still, amongst its features, you obviously now have the ability to run 4.31 firmware which is at least a slight leg up from what we have seen from other groups, and there are also included web scene sources, a full pkg manager, and tools for converting between CEX and DEX. This should install on any CFW 3.55 and up as long as you’ve got QA Flag enabled and System Update Debug on as well. From there just place the PUP in an update folder on USB and update from a support storage.
It should be noted that bricks have been reported in some cases so use at your own risk. Also many users are reporting that this is not true 4.31 as indicated by the CoreOS files. If you can look past that though, here is a feature-rich CFW for you.