With the introduction of the 552, the 442 is officially retired. Here's what Sound Devices' Jon Tatooles had to say on this solemn occasion on the RAMPS newsgroup: 

It is with excitement and reflection that I put the very last two 442 mixers ever produced into our "museum" (a shelf in an equipment  cabinet). They join the first product Sound Devices ever produced, an  MP-1 (1999). The 442 is now discontinued, but will continue to thrive  with the many units that are in regular use all over the world.