I am here to support SLI.  I had my rig set up a week ago with a single 7800 GTX, beatiful GFX and everything.  Now, I put the second card in, and what\'s the difference you ask?  Graphically, the game looks the same, but the frame rate is great, and it loads a LOT quicker for some reason, plus there is virtually no slow down with the graphic options maxed out.  (Game tested was Farcry)