From the FAQ :
What does MOVIM have that other social networks (Facebook, MySpace...) do not have ?MOVIM is overall free, that means you can learn how it works and modify it to your needs. This garantee a total transparency on your personnal data managing and the way they are used.
MOVIM is furthermore decentralized, that means your data will be on your computer or on a trusted server, you have the choice !
Its system, composed in "blocks", allows you to customize your MOVIM content according to your desires.
Go and see for yourself!