There was a nice comment by the writers of "Silicon Valley" about attending TechCrunch Disrupt and seeing a sea of Macbooks. The *perception* is that the majority of top startup developers are all Mac OSX users. Microsoft wants to change that. To Surface Books if possible, but wouldn't give a rats if they were running ThinkPads, Dells, HPs or whatever running Windows OS.
If Microsoft can get some of that that TechCrunch Disrupt audience to shift across, they change the perception of Microsoft in a very important demographic. Maybe they get a few more of that audience using Azure over AWS. Maybe a few of them start using other Microsoft services where it makes sense, rather than the default perceived attitude of that audience being to avoid MS products like the plague.