Google Desktop for Mac?

Google Desktop is available for the Mac. There’s even a demo video.

But what they don’t mention anywhere is why I’d want to use Google Desktop when Spotlight already does such a great job on the Mac.

I get that it searches your Gmail. That’s actually a nice feature. I have Mail downloading my Gmail through to my local system so Spotlight can see it, but having it index the mail right there in Gmail would be nice.

But I’m not willing to have two content indexes of all the stuff on my computer.

If Google Desktop uses the Spotlight database for the local system, then I’ll use it. But Google’s expertise is search, so I’m guessing they wouldn’t use the platform’s built-in search. Anyone know for sure?