Embedly have kindly shared some internal data on how many of the URLs they process contain Facebook’s Open Graph semantic metadata. It’s massive.
They show that nearly half of all their traffic is enriched with this additional semantics – an impressive amount considering that the initial Open Graph released in 2010 was limited to the point of uselessness beyond the very few nouns such as movies, actors, restaurants and the weird choice of three groups – “Cause”, “Sports League” and “Sports Team” (good luck if your group was anything else!). It was only earlier this year that the updated Open Graph allowed for any nouns and, more excitingly, verbs or “custom actions”. This has lead to an surge of sites using the new semantic metadata for both fun and serious information. Although of course, this surge was delayed somewhat as we all ground our teeth and cursed them for completely changing the tags we’d just finished embedding in our sites – but thet’s proprietary systems for you as Tim Berners-Lee will quickly point out.
As Embedly notes, this high figure is massively skewed by the fact that they’re only looking at URLs which have been shared – mostly from Facebook-optimised sites. However it does show the direction of development these leading edge sites are pushing in, which is a promising sign for the rise of the Semantic Web.