The hashtag thing gets old very quickly. It also has become meaningless because people now make hashtags out of too many things. I have everything I post from my Facebook author page and the two group blogs I'm on set to post to Twitter automatically. The only time I'm on there manually is to thank people for tweeting something about my books, or for retweeting a blog post I've sent there.
I'm on Facebook a lot, but even that I have down to a science.

For example, it's rare you'll see me post about whatever I'm eating, and I try to keep the drama down to a small roar, when it's there at all. I've unfollowed several friends since November because they post nothing except political crap. Yes, it affects me as a US citizen, but I'm so sick to death of it that I can't even read the legit stuff right now, let alone all the questionable stories.
People who are constantly on social media baffle me. Don't they work? Don't they have to do things like clean their kitchen or run to the grocery store? I'm on a computer all day long at work, and I'm on this laptop the rest of the time. When I come home after work, unless I have a release the next day or just received a new cover, I don't want to touch a computer or my smart phone. I need to unwind and relax.
