[ghaff]

Interesting idea and somewhat akin to how music streaming pays the artists (well, the labels mostly). The challenge, as you allude to, is that software is a lot less homogenous. You only do one thing with a song--listen to it. You use software in a lot of different contexts and it's not obvious that time running is going to give equitable results. And Pro-ishness is also very context-dependent. For me, Final Cut might be a hobby thing. For you, it might be something you depend on for your livelihood.

That said, I do think we're going to see more experimentation with subscription models. Adobe's Creative Cloud is one example. I could imagine some sort of aggregator of games as well.