Dark_AleX just released an update to the custom firmware 2.71 SE. However the new revision C does not include most of the promised features.

Here are the features:

- Loading plugins from the ms:
Plugins from the ms are loaded from the folder ms0:/seplugins
You need to write two text files inside that folder: game.txt and vsh.txt
These files have a module path in each line to load with umd games/homebrew and with the vsh
respectively. A maximum of 5 modules is allowed in each one.
Once the files game.txt and vsh.txt are created, you can enable/disable each plugin in the recovery menu.
Note that if you have too many modules loading, the xmb or the game may not start because of lack of memory.

A usbhostfs plugin for SE is planed in the near future.

- speed change:
It has not been implemented in SE yet because it was causing weirds problems at the moment in which
the speed change was done. Probably it will be implemented in the future on other way...

At the momento you can use one of those plugins that before were installed on flash and that now
can be installed in the ms.

So, basically the only new feature is "loading plugins from MS", the rest will (hopefully) be in future revisions.