We've just published the latest DBpedia Usage Report, covering v3.3 (released July, 2009) to v3.9 (released September, 2013); v3.10 (sometimes called "DBpedia 2014"; released September, 2014) will be included in the next report.
We think you'll find some interesting details in the statistics. There are also some important notes about Virtuoso configuration options and other sneaky technical issues that can surprise you (as they did us!) when exposing an ad-hoc query server to the world.