I also like this. But I wonder why both the SLK and the boxter (and even the cayman), out-sells the Z4.
Imagine you were BMW, and trying to make a profit. What would you have done differently? You make the best looking roadster, put the most award-winning engine inside. You tune it for that everyday sports-oriented driving BMW is know for, and then the world's leading car show (top gear) comes out with a stellar review and firm recommendation. Even Jeremy Clarkson says he certainly perfers it over the SLK and the Boxter. Yet you keep your feet on the ground, and do not price it any higher than those alternatives.
If I was employed by the marketing department responsible for the Z4, and I hadn't already been transferred to the new M(arketing)-division, I would be thinking very seriously about whether trying to sell cars, that are truly sensational, is really worth it anymore.
Also I would be beating myself pretty badly for betting on Pitbull & Marc Anthony while letting the SLK in on PSY and gangnam-style.