Well, I think it's obvious who will pay, we are. Microsoft want a rerun of Office 365. So the 'free' version will be limited in many ways, and the full one will be subscription.
MS want a subscription model because there are plenty of people quite happy with 2000,XP,Vista,7,8 as it is and they get no money from it (mostly it costs them money). So get everyone (as far as possible) onto 10 by making it 'free' then manipulate people into paying for it.