Floyd - Fair point. I like social media, but having to manage Facebook, Twitter, LinkedIn, G+, Pinterest etc. and now TSU, it might be too much for people. I guess it's about finding the 1 or 2 that work best for you and going with that. Personally...I'm having a play around with TSU. To answer your question, I do make sales through my website and traffic has increased recently and I am seeing referrals from TSU. Whether they are the same people that are buying, I have no idea.
Mike - It is a blur! Be very selective with who you 'Friend' or 'Follow' as that dictates what you see in your feed. As you say, it's invite only just now. This is mine https://www.tsu.co/goofysurfer but everyone gets one when they join.