I doubt it. It applies to most giveaways of any kind (free posters, free calendars, etc). They usually only accept entrants from one country or equivalent legal entity. I expect it's because of variation in contest-related laws between countries, tax laws, etc.
Yes, in some countries if you advertise a public contest you first have to register it and vet it with your government, who then make sure everything is done fairly. That is something google simply cannot afford to do.
I am sure they will find a way to reward jamendo somehow. They'll invite the guys for a formal visit and give them business cards in the shape of netbooks, at the very least.
