Twitter can be a strange place sometimes. I’ve been on Twitter with my @JeroenFM account for quite a while now, since November 2009. In June last year I created my @JSteenbeeke account, primarily to stop bothering friends and co-workers with writing-related tweets (and to follow back other writers without clogging up my main timeline). Those that did want to read my writing news simply followed both accounts. Overall, I think my experience with Twitter has been pleasant.
What it doesn’t do well, is help authors sell books. I base this opinion both on my own experiences, and on anecdotal evidence from the people at the Kindleboards. My @JSteenbeeke account currently has about 100 followers. The vast majority of those followers are fellow writers. Not readers, writers. Most of those writers I do not follow back. If I did, my timeline would be a wall of book advertisements.
My efforts of book promotion to Twitter have resulted in a total of 3 sales, and perhaps a number of free downloads when I was participating in KDP Select. Those 3 sales were through Smashwords, when I offered 50% off with a coupon. I know exactly who bought those copies, as two of them were co-workers, and one was a friend of a friend.
So, Twitter hasn’t helped me sell that many books, and many writers agree Twitter isn’t an effective tool to reach new readers. It’s not that hard to figure out why: when you’re looking at Twitter, are you looking for stuff to buy? Or are you looking for interesting tidbits of information and/or images? If a person you are following does nothing more than tweet "buy my book", does it invite you to buy the book, or to unfollow the author? In my case, the latter.
If an author starts following me on Twitter, a number of things can happen:
To make a long story short: don’t spam your books on Twitter. You’re not buying other people’s books that way, so why should someone else.
Ok, enough for now, rant over