Elop, who has held executive positions as Microsoft, Juniper Networks, and Adobe (, is an obvious candidate to succeed Ballmer based on his resume. He knows the technology industry and Microsoft in particular, having led the all-important group that makes Office. Most recently, he's been trying to turn around Nokia, the troubled mobile phone maker. However, his strategy of adopting the Windows operating system for Nokia's smartphones hasn't exactly been a hit with customers, and it will likely count against him. )
Investors cheered news that Microsoft CEO Steve Ballmer will retire, but there is no obvious successor in line.