“NILFS2 (New Implementation of a Log-Structured File System Version 2) is a very promising new log-structured file system that has continuous snapshots and versioning of the entire file system. This means that you can recover files that were deleted or unintentionally modified as well as perform backups at any time from a snapshot without a performance penalty normally associated with creating snapshots. In addition, there is evidence that NILFS has extremely good performance on SSD drives.”
Source: http://www.linux-mag.com/cache/7345/1.html
I wonder if this is what Ubuntu/Sandisk have been working with to get SSDs flying.