I disagree. "The people who said that" are right. Integrated graphics will replace most discrete GPU's from the market, just like the "mobile" discrete GPU's have replaced most PC GPU's from the market (meaning not too many people care about them anymore).

Integrated graphics are just now becoming good enough to play HD video and such, and most people don't care about playing latest games on their laptops. The "ultrabooks" trend should also push the discrete GPU's out of the market even faster.

But of course professionals will still use discrete GPU's. I wouldn't worry too much about Nvidia anyway. They are leading the way in the ARM chip market, and that is ultimately the future for "personal computing" chips. So even though both Intel and AMD are disrupting Nvidia with their integrated graphics, Nvidia is also disrupting them back in an even worse way in the mobile market.