For the longest time, I was a huge advocate of Facebook for business. It seemed to draw a LOT more referral traffic than any other social site. That is until they changed their algorithm. Have you noticed that your Facebook business page is getting less likes than before? Michael Stelzner wrote a great overview of the change awhile back called Facebook Marketing Declines: How Business Should React.
Ever since the change, I’ve been moving more towards Twitter. The major difference is that Twitter is completely unfiltered. You don’t have to promote your tweets if you don’t have to whereas Facebook pages are encouraged to boost their posts in order to reach your audience.