What we need is a reference for data costs over the world.
For example,
Three UK:
_roughly_ £1.80/mb for EU
& £6/mb for rest of the world.
Vodafone UK:
Europe: £1 for each MB up to 5MB, then £5 for every 5MB after that
Rest of the world: £3 for each MB up to 5MB, then £15 for every 5MB after that
Forget the details, keep it simple.
Even here doesn't mention data roaming on their comparision:
http://www.roamingsims.com/ > data roaming on the left side
