Germany doesn't allow dual citizenship and I am not sure if I want to surrender my German citizenship. Also, as a member country of the European Union I could life and work in 16 European countries - I don't think I want to do that, but it is nice to have that option available. Anyhow, in Germany politians are discussing the dual citizenship for some time - so far no luck, but I hope that will change in the next five years.
Who knows maybe our grandchildren will get 'Earth' citizenship allowing them to live in any corner of the world that they like.