I can think of 1 noticeable place where 2gb helps me on 1920x1200. That's in Dirt 2 in the LA stadium due to the massive crowd size it made a 1.2gb card become a slide show, but my 2gb runs it well.
It seems to help a little at the end of the Dragon Age origins expansion as well. Otherwise, I don't believe I'm gaining anything with 2gb's now.
That's not to say that games coming out in the next year won't be able to use it more.
That certainly makes sense. I want it to still play games well into 2 years from now, the reason for the 2gb of VRAM.