For those who are going to upgrade their PMW-320 with the new firmware, here's a little hint:
the instructions say that 'no message will appear during phase 2 of the upgrade' and so you will expect that is all what's going to happen. Just to put you at ease, there are a few more thing going on during phase 2: the whole display goes black, as if the camera switches itself off, and the tally light comes on, as if it were recording. So don't worry if this happens, it's normal. Do NOT interrupt the upgrade at this stage, it continues for another 15 minutes or so.

The upgrade is here: http://pro.sony.com/bbsc/ssr/micro-xdcamexsite/resource.downloads.bbsccms-assets-micro-xdcamex-downlo

I just noticed that the upgrade brings a change that is not mentioned in Sony's description: before the upgrade assignable switch number 2 (the sliding one) could be programmed to do a number of things, such as switching zebra's on and off. After the upgrade, one can only choose between (off) and (picture cache). Not an improvement, if you ask me...