For a long time now I've been saying that social media sites are only valuable if there is a quality audience. Large volumes of *monkey chatter* amounts to nothing, unless all you're measuring is the type of activity that is all about *LOL hehehe*. Yes, I am talking about Facebook here. Hopefully you have long since realized that Facebook is just sound and fury, signifying nothing. Post pictures of your cat, or your cousin's baby there, if you want to, but feel free to safely ignore it for business purposes. Unfortunately, the same thing has happened to Google+, so you can ignore that, too.
But you do want to continue to have a presence on Twitter and on LinkedIn. And this is how you do it now -
Start with LinkedIn and post there. Personally, I write a blog post and copy the URL to there, which is best if you have time. If not that, at least post something on LinkedIn occasionally. When you do post it on LinkedIn, be sure to check the box that has the logo of Twitter. It looks like this
So post on LinkedIn and it automatically does a Tweet on Twitter. That's all you need.