Use whatever social media you want. Feel free to use it on company time. Just use common sense and remember that if you publicly identify yourself with the company’s brand then act in a manner consistent with that brand. It’s in all of our best interests to do so.
The above quote is somewhat out of context, though maybe not in the way you would suspect. Michael Hyatt, CEO of Thomas Nelson Publishers, lists five reasons why your company doesn’t need a social media policy. Go read the list.