It's not just European government that's opting for open source. Today the NSA (the super-secret spy agency in the US) have announced they are joining in with OpenSolaris. Barton has an interview that explores this more. I think we'll see more and more government engagement as the adoption-led market takes hold.

Using Free software from open source communities makes perfect sense for governments, and not just for the obvious reasons of up-front savings on license fees.