What about google desktop search? No mention?Well, I don't use google desktop, so I wouldn't be in a position to analyze it. Feel free to contribute if you're familiar with it!
I've been using GDS for a while, and it's pretty decent. The live searching feature, though, it 100% robust and fully capable. It's lightning fast, it indexes pretty much everything one would want (and you can exclude certain items/drives/etc). In the scope of this article, though, the find-as-you-type is first-in-class. My .02. Thanks for the write-up, I'm currently trying to make my way through the Opus 8 manual. Looks good so far.