The companys official press release says that the previous CEO, Leo Apotheker, officially stepped down from his post (although its likely that he was forced to resign by HP's board of directors). He was in the CEO position at HP for less than a year.
In addition to this news, HP has named Ray Lane to be the executive chairman of HP's board, replacing Meg. Whitman says in the press release, "I am honored and excited to lead HP. I believe HP matters – it matters to Silicon Valley, California, the country and the world." Whitman was previously the CEO of eBay, and helped them grow from a startup to the online destination it is today.
Whitman has her work cut out for her as she takes charge of HP. The company is in turmoil thanks to the choices made in the past year, especially in the last few of months as it discontinued its extremely hyped HP TouchPad and announced it was no longer going to sell any more webOS-based hardware.
More importantly, HP announced that it was considering a plan to spin-off its enormous personal computing business -- still the biggest in the world -- into a separate stand alone company. It's unknown at this point if Whitman might decide to take HP in a new direction and have the company reconsider both its webOS hardware business as well as the HP PC spin-off idea. HP's stock price surged up in after hours trading on Whitman's CEO announcement.