I don't want to pour cold water on the inspirations that these fantastic initiatives can provide. But (you could tell there was a but coming, couldn't you?) we should also be cautious about how easy it is to 'read across' from software coding or populating a knowledge base to the often quite fuzzy and diffuse settings where civic innovation takes place. To give one crude example: software either runs or it doesn't, it produces a verifiably accurate output, or it doesn't; working in social and civic spaces often isn't like that.
If we're going to learn the lessons of Open Source and successful wikis, we need a relatively fine-grained analysis of what it is about them that makes them work, and how transferable these lower-level features might be to the kind of work we're tackling. One of the best I've come across is Paul Duguid's analysis of so-called 'peer production' and what he calls the 'laws of quality' (in Open Source, one such law is "given enough eyeballs, all bugs are shallow [easy to fix]") in his Limits of Self-Organization paper. It's quite a long in-depth paper that covers Wikipedia, Gracenote and Project Gutenberg. If you haven't got the stomach for that, here's a briefer commentary and summary by Seb Schmoller.