This post represents two major ideas, first of "app stores," and second of "Sass" or "software as a service," which seems to be the prevailing business model for contemporary technology companies that aren't stuck in the 80s. With reflection on free software, open source, and the technology industry as a whole. Because that's sort of my thing.
On the one hand the emergence of these tightly controlled software distribution methods represent a fairly serious threat to free software, as does SaaS particular insofar as SaaS exploits a GPL loophole. On the other hand these models, potentially, represent something fundamentally awesome for the technology and software world, because it represents a commonly accepted paradigm where users of software recognize the value of software, and the creators of software can get compensated for their work. It's not without its flaws, but I think it opens interesting possibilities.
Free and Freedom
Obviously app stores present a quandary for those of us involved in the free software world. On the one hand app stores are not free, which is a trivial complaint. It's not the cost, around which "free software" is truly centered, the true failing here is that creators of software cannot choose to participate in an app store system and distribute source code: the interaction and relationship between developers and users is very scripted and detached. These issues all grow out of the reality that app stores--by design--are they're controlled by a single institution or organization.
Which isn't itself a bad thing--there are contexts where centralized organization means things get done more effectively, but centralized authority is not without risk. So while this question isn't resolved, it's also the kind of question that requires ongoing attention and reflection.
Paying for Software
At the same time, I think it's very true that the "app store model" and indeed the more successful "Web 2.0" business models (e.g. new businesses on the web, post-2003/2004) have posited that:
Software is a thing of value that users should expect to pay for.
And that's not, at least to my mind, a bad thing for the software world. Free or otherwise. Or not always a bad thing, particularly for end-user software. For larger pieces of software (in the "Enterprise") money is largely exchanged for support contracts and for services related to the software: custom features, IT infrastructure, etc. For end user software, support contracts and custom features don't tend to make a lot of sense in context: so perhaps moving back to the exchange of money for software isn't a bad thing.
The connection between "value" (which software almost certainly creates), and currency in the context of software is fraught. Software isn't scarce, and will never be (by nature.) At the same time it does have value and I think it's worth considering how to arrange economies that involve exchanging money for software. There are a lot of factors that can effect the way that app stores might work, and I think given the possibility for causing interesting things to happen we shouldn't dismiss them out of hand.