I think it has to do with their confidence in their brand-name recognition and the fact that even with all the 5xxx series GPUs AMD has been pushing since September, nVidia still has the majority of the GPU market-share. (As far as the consumer desktop market-share is concerned at least.)
I remember watching an interview with Jen-Hsun Huang (nVidia's CEO) a while back on Charlie Rose and Jen-Hsun mentioned how nVidia likes to think of itself and their brand as "Nike", as something for hard-core gamers. While I don't agree fully with that analogy, some of it does ring true. Many times when I mention keywords like "GeForce" or "nVidia", even when talking with the non-enthusiasts, they usually know that I'm talking about GPUs or video cards. While keywords like "Radeon", "ATI" and even "AMD", well those keywords many times result in blank stares. You can say a lot about nVidia and their products but they sure have their brand name recognition taken care of.
LOL, that's what my younger brother knew. He knew what Nvidia was, but he didnt know what ATI or AMD was.
They (nVidia) have been actively pushing this 3D stuff since ...forever. I still have two sets of 3D glasses somewhere in storage. One of them I received with a purchase of a ASUS GeForce3 TI 500 back in 2001-2002, it came in the box, and the other set I received with a nVidia sponsored game "Bridge Commander" also back in 2002. They have been at this for a long while. Interestingly though, nearly 10 years later, I never bothered to plug-in either of them. It just seems sort of corny, a throwback to the 1950s B-movie cinema.
Wake me up when they come up with true-3D visualization along the lines of consumer/gaming grade holographic displays and what not. 3D glasses are for the old folk, at least that's how I see it.
I've been using 3D since Geforce4 Ti4200 in 2002 with shutterglasses that were bundled with the card. 3D was actually avaialbe a few years before that. ATI has never really bothered to support 3D, and NV kinda stopped supporting 3D for a while after making it exclusive for the Zalman monitor after the 7900GTX was released. I had to hack the drivers with nHancer for 3D to still work with my 8800GTX (by the way, the hack would not work for G92 or GT200 cards), so I can still use those cheap wired shutterglasses that can be bought off ebay for only $10. I'm actively boycotting NV's Geforce 3D Vision wireless shutterglasses that retail for a ridiculous $200.
Ever since CRT monitors were on the decline, with the lack of 120Hz LCD monitors, cheap 3D solutions were not viable for most people for several years since (other than the god-awful anaglyph red-blue glasses that I used to play games on the LCD monitor, like Condemned: Criminal Origins.. it's a great game that uses the same engine and textures as FEAR.. actually better than FEAR in many respects. The game is dark and gritty, and is almost colorless, so using red-blue glasses just for that game was not bad, really.
Samsung is working hard on making 3D TV's, but I think that they are still going to require glasses. It'll be a bigger problem for people who already wear glasses, but the more 3D tech gets adopted, the sooner we'll be seeing a truly 3D display that does not need glasses.
