Here is an interesting post from Gautam Ghosh entitled Driving Enterprise 2.0 behavior change where he points to an article Not every blog has its day in the Sydney Morning Herald. The article makes the point that "Fostering collaboration in the workplace involves more than just building platforms".
I had to smile as its really about E2.0 folks learning what KM folks have long known.
I learnt this myself with Lotus Notes 1989 - 1999 (in fact it was one of the prime motivators for my moving away from technology and starting to focus more on the people side of things); KM folks then learnt it 1999 -2009 and now the E2.0 folks are learning it.
To my mind, the lesson: "Don't implement a technology tool (impose it on people) and expect them to see the benefits and use it. Work with them to help them solve their problems and introduce them to new tools that you think will help. Let them select the tools that work for them. They need to have ownership."
But it takes time ... 20 years or more and people are still learning :-)