Google could help kickstart that ecosystem by offering a promotion category for "Best Free/Open Source apps" in Play. Only apps with a GPL compatible license and fully buildable from a public repo are eligible.
I'm not sure Google has the incentives in place to be interested in this, but it seems like a perfect fit for CyanogenMod as they try to grow as a platform.
The incentive is that Google will benefit form having an ecosystem of high quality apps. A good ecosystem lowers the bar to creating high quality apps - the non-app open source software ecosystem is pretty conclusive proof of that.
But you're right - CyanogenMod is probably a better forum for such an ecosystem to bootstrap.
Hmmm, maybe I should have appealed to Google's strategy rather than their incentives. An APT/RPM style model strikes me as counter to the prevailing direction that Android, and Google more generally has been moving.
I think that from their perspective, mass market users don't care about license terms or free-ness as in freedom. They seem to care about free-ness as in sticker price, even when it comes with prohibitive in-app purchase requirements. If we look at mass market targeted app stores based on APT-like repository systems, well, all we really have is the Ubuntu Software Center. And that isn't clearly better than the Android Market to the mass market user, and I would go further to claim that the inverse is true. So I can't see strategically why Google would change direction toward an Ubuntu Software Center style direction, and the higher quality but less user friendly APT/RPM/pacman is just a complete non-starter.
But CyanogenMod seems to have reached its market position by appealing to the ethics of openness. So it makes sense given their prevailing strategies. They also have a history of providing relatively open/customizable alternatives to Android components, and an app repository in the tradition of APT/RPM would fit right in with their past initiatives.
