No easy answer. We have worked with hundreds of businesses on this front. Facebook is good and worth it if you target correctly. Twitter is excellent for reaching reporters and bloggers. Instagram is good for the fashion, lifestyle, artist, foodie audience. There are sooo many channels to choose from. Pinterest is excellent in terms of beautiful consumer packaged goods, fashion. Choose your channels and strategy according to how you are targeting. They are all valuable for their own reasons. Your owned content is the most the valuable and effective way to reach people. So that means writing excellent blog posts and publishing them on a consistent schedule -positioning yourself as the SME in your space. I agree about Reddit -it's insanely powerful but if you're not authentic and you're there to sell they will boot you out in a heartbeat. Vine, Snapchat, Reddit, Google+, YouTube, Feed, Thumb, Medium, Chirp, Learnist, RebelMouse, Yammer, Ning, Tumblr... and I could list hundreds more. There are thousands of tools and channels. Find the right one(s) for your company and create a strategy around those channels. Pitching your story to high profile blogs or websites from an editorial standpoint is also a good idea. PR alone or social networking alone won't result in being propelled to fame. 'Fame' comes when you have that magical cocktail of opportunity, timing, preparedness and you're offering something that truly sparks people's imaginations. Happy to hop on a call about any of this. Good luck!