There are three Cabinet agencies that cover most immigration matters - Homeland Security, the State Department and the Department of Labor. We already know that Hilary Clinton is leaving her position at the Department of State and that Senator John Kerry will be her replacement after his likely confirmation by the Senate. I wouldn't expect to see many changes at the State Department as a result of the change in leadership.
Hilda Solis announced this week she is leaving the Department of Labor. And while I don't have a negative view of Secretary Solis generally, I think most immigration lawyers would agree that at best she's neglected the immigration programs run by the Labor Department such as PERM for green cards and the H-1B Labor Condition Application. At worst, she's complicit in the steady worsening treatment of employers, immigration lawyers and, ultimately, immigrants filing applications with the Labor Department. The White House has indicated it is interested in making the immigration path smoother for many who can contribute to economic development in the US and, indeed, they've started to make changes at USCIS reflecting this mission. But the Labor Department plays an important role fixing problems there is also important if we're to retain these bright immigrants.
We've also heard that DHS Secretary Napolitano is the leading candidate to take over as Attorney General. And that would create an opening at DHS. Given the DHS Secretary is in charge of USCIS, CBP and ICE, this position is hugely important to the immigration system.