If Sony & Microsoft decide to go through with this. It'll probably take me even longer to go out and buy a PS4 (I'm not a huge fan of X-Box anyways). It took me until Black Friday 2011 to buy my first PS3. Plus, call me a cheap ass or whatever. But most of the time I'll be my games used from GameStop. Unless it comes with some content I really want with new copies. So if this does infact happen. Nintendo will be getting more of my business (unless they decide to go with it too).
Really bad idea if it does happen. I'm sure there will be people that'll still buy the console, but a few will probably think twice about buying one if that's the case. I mainly buy games new, or on the day of release, but if I see a game that I was interested in but never bought and it's going cheap on Ebay or Amazon(Used) I'll buy it.
Which is another point, the move is mainly to attack companies from selling Used games at around the same price as new ones. It actually stops the consumer from selling their own stuff, at a higher loss so once you're done with it you can't do anything with it.
Also guessing you'll be unable to borrow them from friends?
What happens when your 720 dies? Do you have to replace your entire collection?
My guess is that the games would tie to your account, not to the system. If they tie to the system itself, then the question you raise is a good one. I like Steam, but I also owning a hard copy of my games and having a collection to physically look at above my TV. Seeing damn near everything go digital sucks.