As a custom computer builder and retailer, we took an opposite stance. Up to this point there has almost always been a single video card that can do what SLI is capable of, so we never recommended SLI to anyone except the high-end buyer who was going to start out with it. The reasons were simple. Most 6600s can't SLI, Two 6800GTs may not even beat one 7800GT and the only reason to have that much power is to run very high resolutions like 1600 or higher and all cards before the 7800 series don't maintain good frame rates at that res or higher. So, it has been mainly for the elite who want two 7800s.
Now that brands can be mixed, and with the rumors of Nvidia offering a full lineup of 7000 series cards, perhaps there will actually be a point to getting one mid range card and another later. Then again, at the pace technology changes, maybe not.
EDIT - Oh, and my two XFX 7800GT cards for SLI just arrived this morning. I'm in the exact same situation as the article. I have to add another waterblock, and I just got a 2405fpw and gaming without at least 4xAA in 1920 just doesn't do it for me. So, it's finally SLI time. The big rebates and free COD2s with each card didn't hurt either.
Now that brands can be mixed, and with the rumors of Nvidia offering a full lineup of 7000 series cards, perhaps there will actually be a point to getting one mid range card and another later. Then again, at the pace technology changes, maybe not.
EDIT - Oh, and my two XFX 7800GT cards for SLI just arrived this morning. I'm in the exact same situation as the article. I have to add another waterblock, and I just got a 2405fpw and gaming without at least 4xAA in 1920 just doesn't do it for me. So, it's finally SLI time. The big rebates and free COD2s with each card didn't hurt either.