A service bulletin was issued in the past concerning the first models of pitot tubes for A320 family. This SB was mandatory for airlines. The had the obligation to change the pitots.
With the older pitots, there were some issues with Air France 320 (unreliable speed indication, etc), particularly for the 320's operating in the caribean (fort de france etc)
The SB issued a few years ago for the 330's / 340's was not mandatory, so some pitots were changed on the Air France fleet, but not the totality...
The NTSB is investigating two more cases of recent 330's who had the same problems as AF447 (but who landed safely).
TAM aircraft from MIA to Brazil, by the end of may 2009
NWA aircraft to Japan, Jun 23rd.