What resolution, and what AA settings? AFAIK, people I know with Ultra SLi and Quadcore setups can't play on Very High on anything beyond 1680x1050.
it's playable @ 1680*1050 very high on an overclocked 8800GTS it's just nowhere near as smooth as I'd like.
not really is the final answer, yes you can turn down the settings and get good fps and have fun but we don't have hardware yet to play it like it was envisioned @ 1680xx1050+ DX10 Very High 4XAA/16XAF wth acceptable/good fps