Well, this looks fairly nasty. Does anyone have experience with this issue? How long has it been around, etc.?

only 64 and 128GB drives. Ours are all 256.

We had about 10 of our 2012 11" Airs have SSD drive issues over the summer as we were updating 10.8 and running all other necessary updates getting the laptops ready for the summer. Apple replaced the drives as they were just getting stuck in a firmware update loop. Guess we are going to have to test our other 200 possibly affected machines now :-(