One thing I'd like to ask, is whether it's possible to add some of these shiny video effects the same way that bump and specular mapping, the detailed terrain option, self-shadows, detailed water, etc. have been done. In other words, lower-end machines can keep details at the current levels, while players with high-end rigs can add those additional effects (HDR, AO, etc). Basically make it a best-of-both-worlds thing?