There is a (very reasonable) opinion around that the cameras operating with such high bit rates at the moment cannot provide IBIS, since they need a solid connection to the heat sink. However, I do agree that the still-oriented cameras from Panasonic (GM1, GH3, GX7 …) must incorporate 24p/25p/30p at least, mic/head jacks and of course a competitive IBIS (except perhaps GM, for which it probably would not make much sense due to the size limitation).

Source: EOSHD forum discussion