Just a thought about the ejectable CVR/FDR issue. How about having a duplicate copy of the memory modules stuck into the vertical stabilizer. It seems that this is the first thing to be shed from the plane, and also seems to float -- not to mention that it is big enough to identify in a search.
Think of the AA A300 crash out of JFK, the AF 447 crash in the Atlantic, and now this Air Asia crash. The first thing found was the floating VS section.