In trying to respond to people who say that social media doesn't work for nonprofits, here's what I say now.
With traditional fundraising we send out letters or invite people to parties and we always have a clear "ask" (as people in the field like to say).
With social media, we have an offer.
With traditional fundraising we ask for money, and, over time, try to build a relationship with our donors and now-friends.
With social media, we offer joining and community, and, over time try to see if members of our community will donate money.
The processes are very similar. We hope that at the end of each path we wind up with a community and with a little money in the bank.
That's why both social media and traditional fundraising are important for nonprofits. They're two ways to accomplish the same goal. I'm hoping that this will put an end to people telling me that "social media doesn't work" because people don't often write a check in response to a tweet.