Blaise Agüera y Arcas, a "respected engineer and software designer at Microsoft," is headed to Google, where he'll be a top-level software engineer.
On his blog, Agüera y Arca wrote:
On one hand, of course this is tremendously exciting; Google is a company of grand ambitions and brilliant people. On the other hand it has been hard—very hard—to detach emotionally from Microsoft. The company’s leadership has been consistently good to me over these past eight years, and it has been a time filled with creativity and growth and good friends. It’s painful to leave behind so many wonderful ongoing projects, and even more so to leave behind such a great team.
The hardest decision of my life.
The move to Google will be a significant loss for Microsoft, and a big win for the search giant, and due to the fierce rivalry between the two firms, it's also a controversial move. Apple, Google, Adobe, and other firms have been investigated in recent years for their policies concerning "no hire" agreements between each other, which may have violated anti-trust laws due to the limits they place on individual employee careers.