I guess the safest option would be to wait for the album to come out and then judge the extent of change after having listened to it.
My thoughts are that MM will definitely be able to put his stamp on the band's sound, and that already on the next album. As for the amount of "change", there won't be a radical change, of course. However, I can't shake the feeling that we're in for an album of musical and structural diversity (especially the latter feel a bit short lately, imo, with some exceptions, of course) and a more liberated approach to it by the band (of which we've been getting some snippets, by JM, for example).
But as I said before, a first judgement on it all will happen after I've heard the new album.