Basically, he'll own the M.T.A.

Chaban:

Still, transit advocates and straphanging pols are hitching their train to the governor, either out of desperation or legitimate belief that he could transform the M.T.A. in ways that have been talked about but rarely acted upon. “It puts the governor on the hook,” Mr. Russianoff said. “It will be his pick running the agency, and he will be accountable for what happens to the M.T.A.”

There are few greater political liabilities than the M.T.A., which is why the Cuomo administration has held it at arm’s length for so long. Even with Mr. Walder in place, he could keep this up for only so long, but now, unable to point to a Paterson appointee calling the shots, the responsibility will be his all the more.

“I want to thank Governor Cuomo and former Governor Paterson for the honor of serving the people of New York State,” Walder said in statement. “The M.T.A.’s transportation system is the foundation of the metropolitan region and we are fortunate to have thousands of dedicated men and women who work so hard to provide these critically important transportation services to millions of people each and every day.  I believe that we have accomplished quite a lot in a short period, with the support of two Governors, the Mayor, a hard-working Board and many others.”

Walder was well-regarded by transportation wonks, and oversaw the nation's largest transportation system during a period when transit dollars were tight.

“In challenging times, we brought stability and credibility to the M.T.A. by making every dollar count, by delivering long overdue improvements and by refusing to settle for business as usual,” Walder said.

During the gubernatorial campaign, Cuomo had been non-committal about Walder's future, but it was widely assumed that his Port Authority counterpart, Chris Ward, would be the first to go.

Walder will take a job as chief executive officer of the MTR corporation, which runs the transit system in Hong Kong.