Google App Engine (and other cloud providers) also places limits on how much you can tweak the server side code. Clearly, there will always be apps that require

Google App Engine (and other cloud providers) also places limits on how much you can tweak the server side code. Clearly, there will always be apps that require some crazy server-side C code or whatever, but for 99% of apps all that matters is whether pageforest has exposed enough in the API to take care of the important stuff (validation, etc.) I'm not saying their API is good enough for this, since they just launched, but from a theoretical standpoint I think the concept is sound.