I think the rev Bs were finally put on the refurbished list for one of two reasons.
1. They finally have sold most of the original MBA inventory.
2. They finally figured out the display issue with rev Bs which many of them had to have. Must finally have all those returned with lines fixed.
No matter what the deal is, I wish they would dump the rest of them and be done with them.
Once the refurbished original MBAs are all gone, I expect the prices to rise on the open market - places like eBay and Craig's List. Right now, Apple doomed all of the original buyers by dropping the price so low, so everyone has to compete with Apple's low prices. So, I fully expect the value to jump once Apple stops selling the originals.
BTW, I don't own an original MBA, so I am not just saying that. I actually would have considered buying one for my daughter for her birthday had the rev Bs not finally been added to the refurbished section.