F2FS is short for the "Flash-Friendly File-System" for Linux. The list announcement describes this new file-system as "a new file system carefully designed for the NAND flash memory-based storage devices. We chose a log structure file system approach, but we tried to adapt it to the new form of storage. Also we remedy some known issues of the very old log structured file system, such as snowball effect of wandering tree and high cleaning overhead. Because a NAND-based storage device shows different characteristics according to its internal geometry or flash memory management scheme aka FTL, we add various parameters not only for configuring on-disk layout, but also for selecting allocation and cleaning algorithms."
F2FS in its current form weighs in at 16 patches from Samsung's Jaegeuk Kim that add around thirteen thousand lines of new code to the Linux kernel tree. At the moment there's been no other kernel developers to comment on this new Linux file-system for flash devices.
This is certainly not the first file-system designed for flash devices. Just back in August was the announcement of the Lanyard File-System, but that really didn't get off the ground much and hasn't been merged into the mainline Linux kernel.