Update: The MC2USB-Tools, called 'PS3MCA-TOOL v1.3' which were released yesterday along with the 'FMCB 1.8c-Loader' actually grant FULL ACCESS TO PS2 MEMORYCARDS from PC!
Here's a list of commands:
Copyright (C) 2011 - jimmikaelkael & 'someone who wants to stay anonymous'
./src/ps3mca-tool <command> [<arguments>]
--mc-image, -img <output filepath>
--list, -ls <mc path>
--extract-file, -x <mc filepath> <output filepath>
--inject-file, -in <input filepath> <mc filepath>
--make-directory, -mkdir <mc path>
--remove-directory, -rmdir <mc path>
--remove, -rm <mc filepath>
--file-crosslink, -cl <real mc filepath> <dummy mc filepath>
--content-key, -ck <disk kelf filepath>
--sign-kelf, -k <disk kelf filepath> <card kelf filepath>
So beside being able to create multi-region-installs and those other features you can see at the other news-post, there are also these features (as of yet) already integrated:
-Get free MC-Space
-Dump binary MC-Image
-Basic file- and directory-creation&access (read/write files and folders from/to it)
Additionally! These drivers and tools might be compatible with other MC2USB-Adapters! However they were only tested on the Original Sony-Adapter!