there are notable variations in social network usage across the EU-5 that are significant for advertisers and marketers. In Spain, for example, social networks already reach a higher proportion of internet users than they do in the UK. Italy too will overtake the UK by this measure in 2012. The UK currently has the third-highest rate of social network usage in the EU-5, but penetration will rise more quickly in France and Germany. From 2013 on, levels of social networking in the UK actually look set to fall below the regional average. Read the rest at eMarketer.