http://www.gamespy.com/gdc2003/korean/

The article talks about Korean gaming habits, but it brings up an interesting thing about Micropayments:

“The economics are different overseas, as well. “A lot of gamers in Korea don’t have credit cards,” explained Nexon’s Business Development Director Won Il Sue. This is where 98% of MMOG payments come from in the United States. So how does it work? In Korea, alternative (and simpler!) payment options are available. People can have their online time or game subscriptions charged to their cell phone bill, or to their land-line phone bill.

Because many Korean users came to the Internet through leasing time at PC Baangs, they also have different perceptions than U.S. users. “They’re used to paying for online content,” Sue said. Pay-to-play games are common – players might pay ten cents to play ten hands on online poker. In another example he gave, players would compete to capture one another in big bubbles – for the equivalent of $.25 cents you could buy a “pin” to burst out of your bubble and keep playing. Micropayments such as this are easy if they’re simply tallied onto your phone bill as you play.”