IMHO the obsession with newer sensors I often read about on forums like this is a little irrational. As far as I understand it is more about the electronics surrounding them and the software that enables things like slightly faster capture speeds or slightly better high ISO performance. The sensors themselves have probably not changed that much since I had my first 11mp back. In fact it seems that noise has gone up with megapixel counts, even at the base ISO.
Sure, Phase has introduced some amazing things like pixel-binning, a type of live-view on the back, wi-fi jpegs etc, but all of this is mostly developments of hardware around the sensor, and/or the software. I haven't seen any huge jump in image quality in the 10 years I have owned various medium format backs. I'm not defending Hasselblad's relative lack of development of new hardware features that may increase convenience or usability, but I think it's silly to get hung up on the sensors being the same as they were 5 years ago, because I really don't see image quality that much better than it was back then. If they can increase usability with the same sensors then who cares how old it is? For me it's about the end product and how easy it is to get there, and for that Hasselblad's pipeline from great lenses through to the fully digital body (controllable via the software) and Phocus's beautiful rendering of colour and detail and ease of use is what I like.
Few professionals need or want more than 40 megapixels anyway, so the lack of a back that shoots more than 60MP is not that bad. Professionals who shoot with old 22MP backs or with brand new 80MP backs get paid the same and the quality of their pictures is just as good once published. The exceptions are museums and large print-makers, and for those guys the big MP backs are great, but present their own challenges with wide lenses or slow multi-shot captures to name a few things.
Ben