I don't understand this. This, to me, looks like the stuff a typical clueless business analyst might come up with by simply looking at charts and stats. "Millions of PCs that aren't game ready would SURELY mean many people willing to pay a high price for such a service, right?"
And if I understand correctly, this mean you PAY $25 for 20 hours of playtime on titles you ALREADY PAID FOR?
For a company that makes GPUs, Nvidia doesn't seem to understand that most people interested in playing graphically intensive games on PC already have, to a varying degree, the hardware it takes to do so. So that leaves the more "casual" players as a target for this initiative, and I question the interest of the average casual player in playing these type of games. I mean, do you know many casual gamers who'll buy a game they don't have the hardware to play it on, and then willing to pay an additionnal hourly fee to play the game they bought?
And let's assume for a minute that there's a financial element here. Would this be a substitute to someone with not enough money to buy a gaming PC? Given that to get a good experience, you'd need a very good (and probably expensive) internet connection anyways, and at least a low-power PC or Mac (why do you have a Mac if you have no money???), and given the fact that many games are also available on consoles (which are much more affordable than a gaming PC), why on earth would someone that understands the value of money would pay for such a service?
I'm sure for some specific people in some particular situation, it could be an attractive solution. But these people would be your ONLY clients. You can't be profitable with such a small effective target market.
Unless there's something I really don't understand here.