I did some interviews with the Labor Secretary to be a few, Hilda Solis, in August of 2007. The video above is a discussion of the Progressive Caucus (forgive the shitty editing, I was experimenting). Here's the other video I took, on on global warming and race.
I'm impressed with this pick. Solis is an organizer within Congress, and has the smarts to build political coalitions among different constituency groups, including the netroots. I could see Labor becoming a department that has to build its own power, since Obama's not exactly going to welcome that perspective to a seat at the table unless Solis forces her way in. As an example, Obama has introduced his 'economic team' and met with it many times, without even having chosen a Labor Secretary, a clear sign that to him, the perspectives of organized labor are somewhat peripheral to his thinking on the economy. In 1992, Clinton had Bob Reich as his Labor Secretary, but Reich was also a part of the President's economic team (though he did become marginalized fairly quickly).
This is a very good pick. Solis might turn out to be an excellent ally.