are you looking for official societies, fan groups, schools/colleges, volunteer organizations? Searching FB is a pain, and while I found a couple of "spanish science" groups and a college of medicine/health, but these don't seem to qualify as "societies". - Mickey Schafer

No idea about Societies, but it may be a good idea to create a list on Twitter - Alejandro Montenegro

At least some scientific societies from the USA (AAAS, ASM...) and the UK (Royal Soc, SGM...) are actively using social media to promote their activities, meetings, journals, etc. I'm trying to find out if any similar, official scientific societies from Spain or Latin-America have started using Facebook or Twitter in similar ways -- although it seems that the answer is "No, they have not"... - Cesar Sanchez

Well, the main federal and state funding agencies of Brazil actively use twitter for promoting their activities (e.g., news on research they have funded). As well as some universities such as University of São Paulo, Minas Gerais and Santa Catarina (and at least +5). I did a random look at some biological Brazilian societies and none were using twitter (did not look all, though), but the Brazilian Society for the Progress of Science (SBPC) and the Federation of Societies of Experimental Biology (FeSBE) do use twitter (some of their journals/magazines also have twitter accounts). Finally, there is the community around the ScienceBlogs Brasil on twitter and facebook. Some links: CNPq http://twitter.com/CNPq CAPES http://twitter.com/capes_mec FINEP http://twitter.com/FINEP FAPESP http://twitter.com/Agencia... http://twitter.com/BVFAPESP http://twitter.com/Pesquis... SBPC http://twitter.com/sbpc http://twitter.com/cienciahoje FeSBE http://twitter.com/FeSBE USP http://twitter.com/usponline http://twitter.com/AgenciaUSP http://twitter.com/reitoriausp UFMG http://twitter.com/ufmgbr UFSC http://twitter.com/ufsc ScienceBlogsBr http://twitter.com/science... http://www.facebook.com/pages... - Bruno C. Vellutini

Wow, Bruno, thanks so much for all the information. SBPC and FeSBE were the kind of societies I meant. It's good to know that the Brazilian academic community is leading the way in social media use in Latin-America. - Cesar Sanchez

Thanks for asking, actually, because I did not know they were using twitter also. Now I do :) - Bruno C. Vellutini

Sociedad Venezolana de Microbiología (Capítulo Metropolitano): @SVMCapMet http://twitter.com/svmcapmet - Cesar Sanchez

Fundación Venezolana para el Avance de la Ciencia (FundaVAC): @CienciaVE http://twitter.com/CienciaVE - Cesar Sanchez