I dropped my cable subscription when I moved to my new apartment last August and outside of HN I've been relying mainly on Twitter to hear about what's happening in the world at large. I've used it to communicate with friends and coworkers, to see what interesting people in the open source community are doing, to communicate with people during conferences such as at PyCon, to ask for help and to help others, and for entertainment.
Yes, there's plenty of hipsters and social media experts that do nothing more than add noise, but the asymmetrical follow model and the ease to start and stop following people means that you shouldn't care. Choose the people you find interesting and it will make all the difference.