If you really want this "social media thing" to be a way of working, then each person needs to pick up the tools and figure out how the tools make sense for THEM.  Sure, you can do training, and introductions, and have the early adopters show others how they use the software.  In the end, though, people have to choose to switch because it makes sense for them.

Mark McDonald on the Gartner blog network says that The nature of change is changing with a new pattern being related to much flatter organizations and wider information flow. He says that change is becoming social-driven, rather than process-driven. Interesting.