I really don't get peoples objections to larger video card memory sizes. People have complained since the TNT-2 days and 16mb -> 32mb.
More memory is a good thing it allows for more content and higher quality content. I don't see the need for high quality texturing going away anytime soon, no matter how good things like shaders and displacement/relief/bump mapping get. In the end (with the exception of shaders, but not all shaders) they need to work on textures anyhow.
As always, the cost will probably be high initially, but will certainly come down as availability of the required ram chips scales up. Also no-one forces you to purchase a 512mb or 1gb card (well except for ATi with their X800XT, but I be there will be a 256mb variant of that also). If you don't want the increased memory, don't buy it.