Cecile,
Looks like you are using the lite social buttons that allow leads to post to social networks. These interactions are not captured in the count of "Socially Acquired". Only leads acquired using the following Social Apps are part of the "Socially Acquired" count -
1. Social Button
2. Youtube video
3. Poll
4. Referrals
Today, the count of "Socially Acquired" leads for a program named "SocialPrograms" is the number of leads that qualify for a smart list like this -
The social app could be in any program, not just in the "SocialPrograms". In a future release, the "Socially acquired" count will only include the leads acquired by Social Apps in the program.
Hope this helps,
Raj