Make sure sure facebook, twitter, etc. is installed and they have to be made by RIM... currently RIM does not allow 3rd Parties to access the social feeds
Look it's really easy, first make sure that the facebook and twitter apps you have are the ones develope by RIM no third party apps, then go to social feed and click on option there you can check what apps are link to the feed, its real simple. Good Luck.
Requires the apps that either RIM has written or the APP that is pushed from the carrier to be installed, to be allowed in the Social Feeds app. Nowheres does RIM mention applications that other writers have put together. Nice if it did, but I don't user other apps anyways.