Wenger's book is interesting to me because it seems a more scientific and technical study of the age-old adage, "It's not what you know, it's who you know." Although that phrase was coined to refer mostly to business, getting jobs, etc., it can also extend to the idea of this book -- companies need to encourage the informal interaction of a community of practice. Networking is what so much of business is anyway. You meet people, you exchange information about things, things improve. The internet makes these communities possible. You see them everywhere, from Star Trek fandoms to the Freelancer's Union. Blogs are a great example. A pundit's blog is updated every day, increasing and evolving the domain of knowledge; the readership and commenters are the community; and the practice they are developing is sort of like the domain, just developing knowledge about issues and the world. Some businesses are now using blogs and incorporating open source technology to expand their communities of practice to the benefit of everyone. This is a great way businesses can be practical about it, but they also need to encourage face-to-face interaction. Like office Christmas parties. ;)