*salts the frog*
Ow, ow, ow!
Just pointing out that if this is the case, you can expect to see more pink slips handed out on this side of the ocean. Makes me wonder what is in store for ArenaNet.
If anything, it shows a good sense of strategic planning on the part of NCsoft's management. An office building right in the middle of a business district in a capital city is a fantastic investment and a good way to diversify your income. If your business is blooming, you can avoid the troublesome fragmentation of your workforce, when certain departments get scattered across multiple office buildings. If things aren't going smoothly and the company shrinks, you can rent all vacated space and still earn a good amount of money.
As for their foreign subsidiaries, I wouldn't expect this to affect them in any way. They won't be relocated to Seoul for the sake of it as it would not solve any real problem. Quite contrary. It would raise costs, complicate acquisition of talent and so on. These subsidiaries are semi-separate entities, operating independently for the most part. Every large corporation has those, including Microsoft, Google and other really big players, and it is natural for them to be spread across the globe.