I agree, I too have been using the star for lazily acknowledging that I either read/liked/acknowledged a tweet which got then mixed up with tweets I marked as resources etc. But I was also thinking about the freemium model here and that if I get a moderately good service for free (apart from the use of my data for whatever purpose they like), then can I really expect to have a say in what they do with the service? And, also, really, should we care that much?