Accident Investigations
According to Crain's Chicago Business last week, United Airlines has asked Boeing and the makers of Airbus for competing bids for up to 150 planes, a sales contract worth US $10-$12 billion dollars. Whether AF 447 went down because of a relatively inexpensive Pitot problem v. a massive problem with the tail fin/rudder design or something equally challenging may impact United's choice.
I used to work for the NHTSA investigating fatal truck and car accidents. The process for aircraft is the same: one uses the scientific method and sets up competing hypotheses that explain ALL of the existing scenarios, and then rigorously DISPROVES these hypotheses one by one with ALL existing factual data (even the LAV message will be investigated). The last hypothesis that cannot be disproved is most likely to be correct. The Pentagon already followed this process, presumably based on the ACARS messages, when they said a bomb did not bring down the plane.
I wonder why the Pitot icing is already the most likely explanation with so few data. The NTSB, I believe, would have raised the issue, but would have gathered more data before they disproved all other competing hypotheses. In my experience with mechanical systems and autopses, the evidence from the a/c remains and bodies will be equally valuable as the FDR (which may have been filtered) and the VDR.