There have been various Swedish and Norwegian sites that have changed Red Dead Redemptions' Release date due to the Ash Cloud (..Again) Growing in the european Airspace. However not all earopean countries have to worry since most countries get their games by Trucks or Freighters. Air mail is only used in cased were it is more expensive to get the freight there by Truck or boat.
However Due to the large amount of pre-orders it could still affect the Stock stores will have around the rest of europe.
One of the Sources i could find (swedish) : Clicky!
Forum Discussion : Clicky!
And i have seen many more including danish sites.