My feeling is that this will be a failed experiment - not technologically but from a driver's view.
In near as dammit 100% of reviews I've read of the new 7-speed manual 911 they all agree it's one gear too many to for clutch driving. You're not going to be concentrating enough of actual driving, and you're never going to be faster than the automated dual-clutch gearbox. They also agreed that in quick bends you're going to come off second-best everytime than when using the paddle-shift.
And as near as dammit 100% of reviewers have agreed the new M5's DCT is the dog's bollocks - i.e. near perfect.
The only reason BMW is doing this is because, for reasons known only to the Almighty, Americans are demanding manual M5s. Maybe they should demand rear leaf-spring suspensions too