I am wondering if Olympus will have to update all the OM-D bodies when the 300F4 Pro is released. If the IS is to be a hybrid using both IBIS and the 300's OIS.....strikes me that a firmware update would be needed for that new IS mode. So that is OK if you stick with Oly lenses on the Oly bodies. But, if you wanted the P/L 100-400, will OM-D bodies do a hybrid IS with a P/L lines in the future? As I remember today if you put on a Panny OIS lens you have to tell the OM-D which IS to use.....lens or body, not both. Will the open interorperabiiity of M43 continue/extend into hybrid IS......of is that where we have to stick with one brand to a working hybrid IS?