Bye-bye, Ballmer. But who's next as Microsoft CEO?

Microsoft is beginning its search for a successor to CEO Steve Ballmer. Here's who might be on the internal short list of possible candidates.

Microsoft is starting a formal search fprocess or its next CEO, following the news that Steve Ballmer will be retiring from that role within the next 12 months.
So who is likely to be on the short list? No doubt there will be both internal and external candidates. I don't know who might be considered outside the company, but I can tell the names that have been mentioned as internal possibilities.
Back in January, in fact, I wrote an article for Redmond Magazine on this very topic. That was before Microsoft's latest major reorg, which created a new senior leadership team.
With that in mind, here's who I'd think is on an internal short list:
COO Kevin Turner: Turner was at one point seen as a Ballmer-backed shoo-in for the next Microsoft CEO. He's not too popular with Microsoft employees, but bean counters seldom are. Turner just lost power in the recent reorg, so I am thinking he's an unlikely pick.
Executive VP of Marketing Tami Reller: Reller joined Microsoft back in 2001, when Microsoft bought Great Plains Software, where she had worked since 1984. She moved to the Windows team in 2007 to run business and marketing strategy for Windows and Windows devices.
Executive VP Tony Bates: Bates joined Microsoft as part of the Skype acquisition, and became president of the Skype Division. With the recent reorg, Bates gained power and became the head of business development and evangelism for the company. Before working at Skype, Bates was a GM of the Cisco Enterprise, Commercial and Small Business group. The Microsoft CEO needs to be a Jack (or Jill) of all enterprise and consumer trades, these days. If I were a betting woman, I'd say Bates is a very strong contender for CEO.
Executive VP Satya Nadella: Nadella has worked across quite a variety of business units at the company. He's currently the president of the Server and Tools Business. Before that, he was senior VP of R&D for the Online Services Division (Bing, MSN and advertising). And before that, he led the Microsoft Business Solutions unit (Dynamics ERP and Dynamics CRM). His most recent job is heading up the engineering group for cloud and enterprise. Nadella definitely has cross-unit knowledge.