NEW YORK (CNNMoney.com) - The executive who is credited with leading a turnaround of America Online's Instant Messenger unit is reportedly leaving to join a venture capital firm.

The Wall Street Journal reports that Chamath Palihapitiya, 29, will join Mayfield Fund, a Silicon Valley venture firm with $2.3 billion under management, in January.

The newspaper reports that Palihapitiya took over the instant-messaging division last fall as the unit faced some lost market share. During the past year, he led the rollout of a new version of the product that focused more on promoting AOL music and other advertising-supported content, according the report.

The new version helped AOL Instant Messenger, or AIM, add to its share of instant-message users and increase advertising revenue threefold, the newspaper reported.

Mayfield Managing Director Raj Kapoor told the newspaper that Palihapitiya's business expertise and his youth will help Mayfield better understand the tastes of young people, who are prime customers for Internet and mobile services.

AOL is a unit of media conglomerate Time Warner (Research), which also owns CNN/Money. Time Warner CEO Richard Parsons confirmed last month that the company is in talks with other companies on a possible joint venture or investments in AOL.

Those talks are causing a sense of uncertainty among many AOL staffers, the newspaper reports. It reports that in August, Neil Smit, who was head of AOL's subscription business, left the company to become CEO of Charter Communications Inc. (Research)

______________

For a look at the interest in AOL from other Internet companies, click here.