This is a win-win deal for a major upgrade (if the confirmation and early leak benchmarks are true) and for those who are on the fence about buying the game. The free GeForce NOW sub is just a cherry on top.
Official YouTube Game Trailer
"… If you purchase one of these new GPUs or a pre-built GeForce RTX 30 Series PC at a participating partner, you’ll get a PC digital download copy of Watch Dogs: Legion, and a 1-year subscription to our GeForce NOW cloud gaming service, enabling you to play your PC games on other devices and when you’re away from home.
This offer extends only to select GPUs made by NVIDIA and our partners, and is available only at participating retailers and e-tailers, a full list of which will be available on our GeForce RTX 30 Series Bundle homepage come September 17th. So before you buy, be sure to check that your purchase is eligible for the bundle…."
and more info here
"…The offer will last up until October 29th, and its available at participated retailers. Word of warning though, the GeForce Now code will need to be redeemed by November 30th, and the one year period will begin from the moment its activated, so you’ve got a bit of wiggle room to get your RTX 3000 series set up before you make use of that code…."