I have been testing E-M5 AF performance. There are still more situations to cover. Also I´m not yet allowed to publish images taken with this firmware (1.0). The clearance will come before the end of February.
One separate issue is AF performance with 4/3 lenses. With the introduction of Olympus new AF system (FAST AF) there was a marked improvement in AF speed from E-P2 to E-P3. This happened also with 4/3 lenses. I wrote about this in my earlier blogs half a year ago. Sadly with E-M5 there is no such advancement above E-P3. S-AF speed and locking capability with E-M5 is roughly the same as with E-P3. Any differencies are so small that they are not worth testing more closely. Olympus states that C-AF does not work with 4/3 lenses. Actually it does with some lenses depending on conditions, but I wouldn´t count on it in any real life situation.
Olympus new MMF-3 adapter for 4/3 lenses is functionally the same as earlier MMF-1 adapter. It only allows the whole package be dust- and splash proof. MMF-1 did not have sealings. MMF-3 is lighter than MMF-1 because of different material choises.
So that´s where we 4/3 lens owners stand. I wished for more, hopefully with the next OM-D body.