I like Pinterest (social network). I have two accounts, one for me and one for my charity, because I think is perfect to communicate the mission visually.
In my country very few people use it so far. For now it is easier to find English-speaking fans, so my pins include a bilingual description.
I have used this site for two weeks. Now in March I shall see an interesting impact with the start of classes in colleges and universities. It is therefore important to haveinteresting and varied boards. Who would want to follow a charity that hopefully is less than 20 pins?
in my work I have many responsibilities. For it does not seem logical to add another social network that is not even more important in my country. But certainly when Pinterest start the Spanish version will be very popular here (and surely this will happen in 2012) and then the NGO will be well positioned.
To communicate the work of a nonprofit organization is more impressive to do it with pictures rather than words. For the current generation visual appearance is very important for it everyday.
On the side of the followers, I think they may find valuable things like photos with an artistic touch on the work of volunteers, old and new posters of our campaigns, great pictures of our fundraising activities, etc.
The experience of your charity in Pinterest may be a failure or at least have a very low profile if you do not consider that as any social network, listen to the voice of others is important and you should always post thinking interact with your followers.