opinion. I hope I don't offend anyone, and of course people are free to disagree with me. But I think if you're going to use social media to promote yourself, your blog, your book, or your business, you need to keep in mind the purpose of social media -- to socialize.
Let's take Twitter. People join Twitter to interact with others. Nobody signs up for Twitter to see a bunch of ads. If your tweets all look like ads, you're not doing it right, and I can't believe it's effective. I once saw Elana Johnson suggest on her blog that no more than 1 out of every 6 tweets should be self-promotion, but I have to add that the other 5 should not just be re-tweets or promotions for your friends' books. If you're not interacting with other tweeters, there's no reason to be on Twitter.
I also saw Matt McNish comment somewhere that "scheduled" and "tweets" should not be used in the same sentence. I agree. Scheduled tweets don't even make an attempt at interaction. Some may link to a blog or an article of interest and be scheduled ahead of time simply because the poster is cut off from Twitter by work firewalls. But most of them are just ads. This was incredibly obvious on the day of the Boston Marathon when the Twitter community reacted and grieved and shared information -- in between "my book 0.99 on Kindle" tweets.
Those authors looked like jerks, even though they were probably unaware of the situation. And while anyone might tweet from their phone first and only afterward check their Twitter feed to see what's going on, a continuous parade of promotional tweets made it obvious that the person was either incredibly insensitive or not really there at all. An automaton was tweeting for them, and in that case, why would I follow a tweet-bot?
At the very least, scheduled tweets should be limited and spaced far apart. A long string of them, promoting your book (and all your friends' books) is really just spam. I stopped following a few people last week because of this.
I saw someone respond to a criticism of scheduled tweeting by saying, "If you're self-published, you have to do this." Well, I did self-publish, so I can say that, in my experience, this kind of promotion never worked. I did a lot of trial and error, and I made mistakes. But I never sold any books through posts that were borderline spam. I sold books by interacting with people. If they were interested in me, they checked out my book.
Yeah, it's more work that way. But nobody said it was going to be easy.