There's already an example of an appdb wiki, in a way; see http://wiki.winehq.org/AdobeApps
I did this because the appdb has ugly URLs for apps, and I was trying to post links far and wide trying to draw people in to helping test photoshop and a few other adobe apps.
If the appdb had nice URLs for apps (and this has already been prototyped to some extent, but not deployed), I probably wouldn't have done it.
The appdb has a few other issues (e.g. threaded discussion is awkward to use, deleting old comments takes lots of clicking and scrolling, screen real estate is wasted at the top such that users have to scroll to get to the good stuff, the way test results are selected and displayed is really confusing, etc) but in general we *need* a structured way to present the data, because otherwise we'd have chaos.
So I like the appdb, even with all those faults, and I'd like to keep it and incrementally improve it rather than pitch it all and go for the chaos of a wiki. - Dan