If we are talking about proffessional advertising photography: 99.9% of people buying and looking at a magazine don't give a shit about micro contrast and tonality. some photographers or art buyers might see the difference, sometimes I do, but i can't think of one single page in a magazine that would have been a better image if a digital medium format camera was used. i see a lot crap postproduction or dreadful lighting or horrible styling or all the bits that make or break a successfull ad. Micro contrast is not what makes a picture saleable. no photographer is booked because of micro contrast and fine detail @100%. i see an advantage for big fine art prints, definitely, but for magazine work i don't.
i very much second bcooters opinion about usability of current Medium Format systems.