2011 growth rates for the US: 1.5% UK: 1.1% EU: 1.6%.[1] Now the EU is more than the eurozone, but with the UK dragging down the non eurozone component, I can only imagine that euro-nations averaged above the 1.6% EU wide average and so outperformed the UK and US by a large margin (more than the 0.2%ppt margin of error anyway).
So a lot of the "growth" is just the economy recovering from the austerity/crisis-related policies. The Eurozone's real GDP contracted 5%, so even if we then outgrow the US by 0.5% every year it will still take us ages to catch up.
[1] http://en.wikipedia.org/wiki/List_of_countries_by_real_GDP_g...