Choi finished the CME Group Titleholders at 14-under-par 274, two strokes better than Ryu So-yeon. It was Choi's seventh LPGA title and second in 2012. She won the U.S. Women's Open in July.
That finish moves Choi from fourth to second in the rankings, forcing Stacy Lewis, who tied for 29th at the Titleholders, to third and Inbee Park, tied for 11th last week, to fourth.
Yani Tseng finished in a tie for 26th in the tournament but retains a solid hold on the No. 1 spot in the rankings. She's been on top for 93 weeks. She and No. 7 Jiyai Shin are the only players to keep the same spot in the Top 10 they had last week.
Tseng has a rankings points average of 11.85, with Choi coming in at 9.32, Lewis at 9.08 and Park at 8.59.
Feng Shanshan, sixth a week ago, tied for seventh in the tournament, allowing her to switch places with Suzann Pettersen for fifth place. Both have averages that round to 7.72
Shin's average is 7.23 with Ryu, who moves up one spot to eighth, close at 7.20 and Ai Miyazato, down one to No. 9 despite a fifth-place Titleholders finish, at 7.20. Cristie Kerr (6.20) edges past Mika Miyazato (6.17) for No. 10.