KOF XIII seems to be doing well right now for a number of reasons. It seems to have made a decent amount of money in the ‘Highest Income for Japanese Arcades’ list which features on SRK’s front page. Here is the URL for those that missed it:
Shoryuken - Tekken 6 Wins Highest Income Award for 2010 in Japanese Arcades
http://p.twipple.jp/data/G/f/e/J/p.jpg
KOF XIII came in at 17th out of 20 - but bare in mind that the game was only measured for 4 months out of 12. If you kept the same points average for another 8 months, it would have ranked about 6th in the list. The smaller table at the bottom of the second link pretty much implies that too.
Lets also not forget that KOF XIII also has a big following in places like Hong Kong, so SNKP is probably making significant income there too.
I hope the momentum continues…