Daryl Beattie interviewed JB and was told that wherever Rossi goes he will go so JB "should" be with Vali next season. Also Stoners old crew chief moved to Honda to do a PR job for them but gossip had it that it was purely to get him into the Honda camp and that Stoner would follow shortly after.
All good racers, be they MotoGP or F1 all need a good cheif/engineer and remember there's no "i" in team and both sports are very much a team thing.