Yep, I admit it, way behind on news. Sorry!
This was announced in several places, but Rob Galbraith's story, “Supercharged High Speed Sync, improved EOS 5D Mark II support in new firmware for PocketWizard MiniTT1, FlexTT5 ” covers it best. Not only is there discussion of the changes, but he includes several videos showing the changes. Well worth the read!
A small portion of the discussion:
“More functional Canon EOS 5D Mark II support With this firmware release, the usability of the MiniTT1 and FlexTT5 with the 5D Mark II is greatly improved, says Clark. In fact, it's equal to other compatible cameras now, including with a Speedlite in the shoe of the transmitter on the camera, which had been the main incompatibility problem previously.
The good news of the paragraph above comes with a large caveat: If you use a fast aperture lens set to a smaller aperture, the timing of the firing of both local and remote Speedlites will sometimes go haywire. For example, if you have a Speedlite in the shoe of a MiniTT1 on top of a 5D Mark II, the mounted lens is an EF 50mm f/1.4 and its working aperture is f/4, all should be well. If you change the working aperture to f/11, and leave everything else the same, the flash will no longer fire at the correct time. The result may be a ruined frame.”
There really is a lot more to read and see in Rob's article.
(photo credit: snap from one of the images in the article)