For me, the S65 represents BMW's last pure effort to linking its racing technology to everyday car engines. A time where "performance" was the only consideration. Where the "means" was just as important as the "ends".
A force induction M will be fast I'm sure, but will somehow miss in delivering the frenetic F-1 feel of a NA motor. It will truly be missed. OR maybe I'll keep her and get the M4 as my "beater" car.