I came across a useful article over at Forrester's Groundswell blog on introducing social web technologies - blogs or communities. No rocket science, just common sense, but perhaps useful none the less.
"What do most companies do wrong when they enter the social world? No, it's not that they're being fake, or don't "get it." It's that they don't really know their objectives."
"Is your company doing its social strategy backwards? If you started by saying "we should do a blog" or "we should create a page on a social network" or "we should create a community" the answer is probably yes."
"It's time to stop doing social because it's cool. It's time to start doing it because it's effective."
To help clients with this fundamental idea, they've come up with a little acronym called POST: People, Objectives, Strategy and Technology. Do it in this order, don't get it backwards!