In it's wildfire-like crazy in acquiring new services, Google has recently purchased wiki company JotSpot. The CEO of JotSpot blogged that he believed the company fit well with Google's model:

"It was pretty apparent that Google shared our vision for how groups of people can create, manage and share information online. Then when we had conversations with people at Google we found ourselves completing each other's sentences," he continued. "Joining Google allows us to plug into the resources that only a company of Google's scale can offer, like a huge audience, access to world-class data centers and a team of incredibly smart people."
How much Google is paying isn't revealed, and whether or not they plan to extend JotSpot's technology into their other services isn't mentioned either.