I have a page for my author activities over on Facebook (http://www.facebook.com/SpeculativeFictionAuthor). Most of my author friends also have their own dedicated pages, and some even have pages for each book they published.
This blog is linked to my Facebook page, since I like to maximize the efficiency of the things i write. Some stuff goes to Twitter and other social media.
I was looking at the charts for my author page today, and even though I have almost 420 “likes”, my posts go out to ten people at the most. This is because Facebook changed their rules so they could wring some money out of every user they can squeeze. I’ve read a couple of blogs where people paid to push their posts to readers, but the conversion rate is miniscule.
My conclusion is it’s not worth your time to dedicate resources to get your words in front of .04% of your readers. Certainly, you can automate things so your blog sends updates, but taking the time to focus on your Facebook pages is a waste of time. You should spend that time writing new material, which is the best way to spread the word about your words. Don’t spend money promoting your Facebook page, unless you have George Takei-level numbers backing you up. For those of us working on building a readership, spend your time where it counts.