I'd like to see a community-run version of the Apple Design Awards.
Anyone could nominate an app, and the developer community would vote on who wins, in just a few categories.
I'm thinking the categories could be a little more user-centric than Apple's. For instance, I don't really care about best adoption of OS X technologies, but something like "best refinement of a common task" or "best default behavior" or "best scriptability" would be interesting, and something that'd be easier to use as a marketing badge...
This is just off the top of my head, so there are probably others. "Least data lock-in"? "Easiest to learn?", "Best plugin community"?