In a three-hour show broadcast live from Tokyo's hallowed Budokan, 23-year-old Yuko Oshima was selected as leader and face of the group, which has been recognized by Guinness as the world's biggest girl pop group.

"The 48 group has high aspirations, and because of that we can go far," said the teary Oshima, after the results were announced late on Wednesday.

AKB48, founded in 2005, is known for its perky routines and high "kawaii," or cuteness, quotient. All of its members are in their teens or early 20s. Every year, fans vote to determine 64 of the most popular girls out of a 237-member pool who are then rotated in and out of four main troupes and several affiliated groups according to their popularity.

The top vote winner becomes leader and gets to stand center of the group in live concerts, as well as lead dance performances. The media attention she receives usually means more endorsements and advertising.

Votes are cast by fans who fill out a ballot to determine the most popular members of the group.

In a stroke of marketing brilliance, the ballots are obtained by buying a copy of the group's latest single - this time with the title "Manatsu no Sounds Good," which mingles Japanese and English and roughly translates into "It Sounds Good in Full Summer."

Some hard-core fans will buy hundreds of CDs to give their favorite a boost. They then proceed to an internet site where they input a number contained in the CD, and cast their vote.

The song, which retailed at 1,600 yen ($20), sold more than a million copies in its first day. The group's CDs regularly top domestic charts.

Experts say the group's popularity derives at least partly from their girl-next-door quality.

"These girls start from the amateur level and are unskilled in singing and dancing. But the thing is that they grow together with the fans," said Hidetomi Tanaka, a professor at Joubu University. "The narrative can be called the growth of an idol."

The "AKB" in the name is a reference to Akihabara, Tokyo's high-tech mecca for geeks, where the group has a theatre. The band's popularity is high overseas as well, with sister groups based in Jakarta, Taipei and Shanghai.

(Reporting by Reuters Television; editing by Elaine Lies and Bob Tourtellotte)

• A Permanent Economic Emergency