I've just got back from holiday and I've read that MasterCard have rated Seoul 9th in their index of Worldwide Centres of Commerce published earlier this month.
London, New York and Tokyo take the top three slots, Singapore Chicago and Hong Kong follow them and Seoul rates just behind Frankfurt and Paris. The survey, prepared by a panel of experts, rates 75 cities on seven categories: Legal and political framework, Economic stability, Ease of doing business, Financial flow, Business centre, Knowledge creation and information flow, Livability.
Surprisingly Seoul ranks 4th in the Financial flow category, ahead of Tokyo, based on the number of transactions in Banking, Insurance, Financial services, Equity, Derivatives and Commodities. That could be related to the fact that Seoul is the major city in South Korea, while in Japan, Osaka, Nagoya, Sapporo and Fukuoka have stock exchanges which were counted separately from Tokyo.
One thing they do not seem to have taken into account are the laws relating to the location of computers for processing banking transactions. These must be physically located in South Korea, which for a multinational bank can be a bit of a hindrance. Switzerland used to have similar laws, but these were relaxed about five years ago. It's another reason Seoul will continue to rank behind the main three centres in Asia and struggle to stay ahead of the burgeoning cities of China and India.