Steve Ballmer, Microsoft Corp president, was in aggressive mode yesterday when talking to journalists about the new appointment of Rik Belluzzo as the head of the Consumer and Commerce Group. Asked about the recent brain-drain of top executives from Microsoft, including the long sabbatical of Brad Silverberg, who’s said to have turned down Belluzzo’s new position, Ballmer was defiant. If someone’s not pumped up, then they should be gone. We’ve got too much to do. Microsoft has had an incredible retention rate, and I expect that to continue by and large. But we have a deep team, and the ability to recruit good people from the outside. Sounds like it could be a blemish on Silverberg’s report.