One real value of Twitter, Google+, and Facebook is the quality of what people you are following post. The other (and larger for me) value is promoting my blog. Every time I write a new blog entry, I shamelessly promote it on social media.
This is probably a crazy idea, but I wouldn't mind if these services had "hybrid" paid services: Pay a relatively small monthly or yearly fee, still see just a few advertisements, but much fewer advertisements than the free versions that are more geared to my interests than those advertisements that might make more money for the companies providing the series.