I have asked this question before, but didn't get an official response from the TOW team.
http://www.battlefront.com/discuss/ultimatebb.php?ubb=get_topic&f=63&t=000270&p=1
However I have tested the demo and it doesn't give anything for SLI users. In fact it works better without SLI. The overall game engine graphic performance is horrible. No way to turn on AA and if try to enable it on the video driver level you got a "slideshow" (2-3fps) appearance of the game etc.