It's rather difficult to start talking about Alexander here in this space. So much has been said in other places. No need to duplicate this here. Just read [A City is not a Tree] to get a feel for his thinking. No need to talk about architecture, his main topic, or about software patterns, covered by WardsWiki in minute detail.
One could go a step further and talk about "social patterns", "community patterns" or "wiki patterns". But in fact, to look for good things, describe them and reuse them is already done and this wouldn't change if we added the hype label "pattern" to it.
Maybe his latest books ThePhenomenonOfLife and TheProcessOfCreatingLife? (volume one and two of the four volume series "The Order of Life") may change this. He doesn't even use the word pattern in it - at least not in the typical sense. So what does he do and how is this connected to MeatBall interests?
In ThePhenomenonOfLife Alexander talks about a quality of things that encloses structural (geometrical, aesthetic) and functional (process) components. He says that all things have this quality in a higher or lower degree and that there is no distinction between them, they are a unity. Although one can't measure it with an instrument it is objectively available through collective subjective judgements, which can be trained. He calls the quality sometime "supporting life", "living" or just "life", depending on the situation. It seems clear that the use of this label changes the meaning of the word life somewhat - many philosophers do adapt language - but its still pretty understandable what he means. He also looks into the characteristics of objects or systems that have "much life" and identifies 15 of these characteristics, which he names (suggesting corresponding OC aspects):
In TheProcessOfCreatingLife? these characteristics are reinterpreted as results of structure-preserving transformations that work to extend and strengthen existing centers. He very intensely argues that living structures do not come from "design" but are the result of processes that always take the wholeness into account and try to increase the value and the strength of existing structures. This can not be done on a drawing board.
Wikis or online communities are also objects created to "support life". We talk about "coming to life" when a community forms and starts to grow by itself without the continuous effort that the founder puts into it during the start-up period. We want to know why wikis fail (many fail) and we want to know how to succeed. Perhaps we can learn from Alexander. It won't be easy, because he always talks about geometrical things - like houses, gardens, tools or pictures - and his thinking has to be transformed to work for online systems. But it might be worth the effort.
The idea came to me during the current discussion around the ideas of LionKimbro. Behind all details I think Lion just wants get his wiki to live and to take the role as a strong center for the Python community. One of the 15 characteristics is named "Strong Center". But there are others that might also be applicable in this situation, like "Boundaries" and "Deep Interlock".