I wasn't able to track down the article but I think its kind of recent...maybe in Business Week. Talks about a company that is charging around 1.3% for world wide remittances when the world bank estimates that average fees from banks and couriers are around 8%. Also world bank estimates world wide remittance amount to about 583 billion per year. Didn't mention bitcoin.
If 10% of the $583 billion is represented in bitcoin, that is about $3,800 per bitcoin. Bitcoin can also be use in online purchase.