Secretary of Labor Hilda Solis announced just now that she's leaving the administration.
Barack Obama is going to be under some pressure on the demographic characteristics of her replacement; with Jack Lew, John Kerry, and Chuck Hagel getting the last three nominations, Democratic constituencies will be expecting women to fill upcoming vacancies. However (and as I've been saying for a week now on twitter), there's an opportunity here for him to solve a problem that the Kerry appointment created. The Democratic primary in Massachusetts could easily wind up selecting social conservative Member of the House Stephen Lynch, which many mainstream liberals would see as a major disaster.
With Lynch presumably running, liberals have a strong incentive to rally behind Ed Markey, the frontrunner, to avoid a split field and the chance Lynch could win with a relatively small percentage of the vote. But they may not want to do that, for a variety of reasons. Lynch is, however, strongly supported by labor. Obama could pluck him out of the House and make him Secretary of Labor, thus solving the problem entirely, and allowing a safe free-for-all in the Senate special election primary.
On the other hand...maybe the Massachusetts legislature should just change the rules and institute a new rule that special Senate election primaries need a 50% threshold, and require a runoff if no one reaches it. That would work, too! And we all know that Massachusetts Democrats don't mind making up the rules as they go along on these things.
And the gender imbalance? A lot better to take care of that with a woman at White House Chief of Staff than the minor leagues of the cabinet. Plus, there's always Commerce.