Just out of curiosity, you do realise that 3d vision, is nothing, it's 3d, that is handled mostly by the screen and the game maker, and needs no involvement from Nvidia or AMD.
AMD are giving up on 3d as they have no intention of paying off every dev to create a 3d AMD game.
Every 3d vision screen is simply company X paying a certain amount of cash to Nvidia to be able to add 3d vision branding at which point Nvidia DON'T arbitrarily stop 3d from working on that screen? That is ALL it is.
Crysis will work fine without the driver, from the game, with a 120hz 3d screen, that's it, that is as complex as it needs to be. Nvidia decide to try and make money from it, lock out those who don't conform and pay game dev's to lock themselves in to 3d vision.
G-sync is no different. Please ask yourself what the screen is doing for g-sync that is so different to now.
Currently right now your monitor receives a new image and stuffs if in the screen buffer while also having a little timing program that gets set to 60/75/120hz or whatever else and simply updates every X ms. G-sync is this screen buffer getting updated, but instead of having a set refresh rate defined by timing, it just updates when that screen buffer gets updated...... the graphics card operates in normal mode without v-sync enabled, nothing else is happening. They want to charge you £100 for this OR they will lock your screen out from working in the driver.
Depending on the prices silicon many screens currently might be capable of this with a simple firmware update, it's utterly, completely trivial to add that mode into future screens which will have new controllers anyway. Nvidia can not own a patent on that. if g-sync is worthwhile(the difference from the absolutely perfect conditions demo vs the game was massive, and the game is all we'd care about) then EVERY screen will be able to do this and the only reason you won't be able to use them is Nvidia blocks it in the driver, as they have done for a decade on hundreds of motherboards for SLI, hundreds of screens for 3d vision and the physx gpu acceleration lock out if an AMD card is present in the system.
This is what Nvidia do, take something "standard", lock out everyone that doesn't pay them, calls it a feature and charges you for it.
People have hacked drivers to make 3d vision work on non 3d vision screens, to make sli work on other mobos, to make a nvidia card for physx work when the main gpu is AMD...... but don't worry. Why do I think this is the same...... why don't you think it's the same?
What g-sync boils down to is literally no difference gpu side, and an absolutely trivial change screen side....... rather than Nvidia go the good route, "hey we pushed them to do this, we improved gaming for everyone, isn't that good". They've once again gone the "this is a minor change, AMD/Intel users wouldn't lock people out so they'll have it free as every monitor maker will do it, Nvidia users, we're going to limit which screens you can use and charge you through the teeth for it..... Nvidia users lose..... no one else does.