Libre / Open Source was about users' freedom to fix or tweak the code they run to their satisfaction, or pay someone to do that for them. If the code runs on a server in a data center somewhere, how does the source code help? You can have the perfect patch but if a distant organization (profit or not) is responsible and not interested, the fix isn't going in. You can fork but you'll need your own server and your own rack in the data center.
Perhaps the idea is that today, or soon, anyone can get a hosting solution to run these great Web Apps of the Future. I think that is way too optimistic.