It amuses me to think of Facebook being David and some other internet business being Goliath. But in the case of recruiter spend on social sites, LinkedIn is most definitely the Goliath and Facebook the upstart David. But could it be that LinkedIn’s own history actually turns out to be its undoing? You see today we all view LinkedIn as having commandeered a massive chunk of the global spend on recruitment marketing. Yet it wasn’t that long ago – circa 2008 – that LinkedIn’s business wasn’t focused on recruiting at all. For several years it was a very fast-growing networking site with no seeming plan to turn that position into the recruitment-led business it is today.