Hillary has officially agreed to the Obama transition team's request that she install former Clinton administration official James Steinberg as her Deputy Secretary of State, and Steinberg has accepted the post, according to a Democrat familiar with ongoing discussions over the appointment.

"It's done," the Democrat tells us.

The move has been widely anticipated since Politico reported that Democrats "expected" it to happen, but it's significant that it's now a done deal.

It means Obama and Hillary have successfully agreed on a major personnel appointment, installing a Deputy that will act as a good bridge between the Clinton and Obama camps. Steinberg was deputy national security adviser under Bill Clinton, but he was also an early skeptic of the Iraq War and a key adviser to Obama during the Democratic Primary.

The Democrat familiar with the discussions says that the Steinberg appointment was fundamentally Obama's decision, but that Hillary is happy with the pick. "She's excited by it," the Democrat says. "He's a knowledgeable longtime public servant. He's very smart, very good."

Steinberg was reportedly the author of a big speech Obama gave to AIPAC during the primary and helped craft Obama's positions on the Israeli peace process and Iran, among other things.

Spokespeople for Hillary and Obama both declined to comment.