Yahoo! Rally Fails to Hold

As part of Monday's changes, Sue Decker will now serve as the company's president and will head up the company in a move that was repeatedly described as a "partnership" between herself and Yang.

But Decker was appointed the head of Yahoo!'s Advertiser and Publisher group, a division formed in a high-profile shake-up in December that was supposed to fix the company's problems. Decker's move left the CFO spot open, a position the company has only recently filled.

Decker will continue to handle the Advertiser and Publisher group. But she will also now handle Yahoo!'s Audience group -- another newly formed unit for which Yahoo! has been seeking a chief.

Yang is highly respected within Yahoo! and is known as a technological visionary, but given his top position at the company, it's unclear how the company will get new ideas at the top -- or really do anything differently.

The same goes for Decker, who has been adopting an increasingly public role lately but also will be hard-pressed for new ways to make contributions at the company.

Semel, whom Yang described as a mentor, also will continue as a nonexecutive chairman at Yahoo! rather than making a clean break. That could further limit new ideas at the top of the company.

Yang said his appointment followed an extensive consideration of both internal and external candidates by the company.