Reddit, and other social websites, seem at their most powerful when a bunch of their users swarm around one issue or another. A good example is when the Portal ARG came out and there was a reddit thread where people were keeping track of the various discoveries happening around the internet. The problem with this sort of thing is that everything gets spread out in different threads when what you really want is a single body of text that contains all the information gathered so far. A body of text that doesn't depend on any one person to keep it up to date.
Given this, it seem to me like being able to flag a post as publicly editable would be a powerful tool to enable this sort of collaboration (opt-in, not opt-out). In this case, a Wikipedia-style approach seems like it wouldn't work. It's not really built for multiple people working on the same content at the same time. Seems like you'd need real-time editing like that found in Google Wave.
So, my impression is that it'd be a big deal if someone created a library/platform that allowed social websites to seamlessly embed a block of text that was editable by its users in real-time.
The Google Wave embed API looks like it aims to provide much of the capability to do this, but it seems like Google's implementation will require any editing to be done under the guide of a Google Wave account, rather than the user's account in the embedding website.
A compromise that leverages as much of Google's code as possible might be a scheme where a wave's content is displayed in the website as plain-text while an edit button opens up the Google Wave client. On the other hand, it seems like a more robust solution would want to avoid Google's servers entirely.
So my questions are:
How feasible of a proposition is this in terms of actually building it?
Are there any open source projects out there pursuing this sort of capability?
Is the wave protocol actually useful here, or am I missing something?
What would you expect the difficulties to be when trying to implement something like this? Are the roadblocks sufficient such that its outside the realm of an unfunded open source project?