So what did it change in the program through the last revisions?

First of all, we now have at the settings the BETA upgrades option (which downloads the latest revision at google code site). The old update progress will use only safe revisions ;)
Actually r851 added a lot of important stuff

* Added BETA upgrades option (to download the latest revisions from google code)
* Added Wii Parental Control support
* Added gui numpad
* Changed GuiText to support password character
* Added lock/unlock icon in the titlebar (to unlock Parental Control)
* Added new wbfs_fat from Oggzee (further speed improvement)

as well as r847

Lots of changes in this revision:
* Added MEM2 support by Hibern
* Better partition support (by oggzee)
* Support for subdirectories in FAT32 (by oggzee)
* Added support for cios 223 and 250
* Added BCA support (go to Settings->Custom Paths) to change the path of the BCA
files (by Hermes)
* Fixed issue with hairless mode
* Fixed issue with IOS_ReloadIOSsafe (by giantpune)
* Added setting to save games in a subdirectory
* Fixed slow startup when loading from FAT (WiiTDB required!)
* Changed handling of new titles a bit (speed improvement)

The loader also now supports headless mode via argv
Of course we also had a lot of bug fixing, and one of them fixed cheating when using alt dol from sd/usb (r856)

Have fun playing until the next update