From an official statement [1]:

Governor Andrew M. Cuomo today announced that New York State will suspend participation in the federal Secure Communities Program to review the mounting evidence that the program is not meeting its stated goal and has serious consequences for witnesses, victims of crime and law enforcement.

The goal as stated by the federal government was to deport serious felons, and, based on evidence to date, it appears the program in New York is failing in this regard and is actually undermining law enforcement. Because of similar concerns, the Inspector General of the U.S. Department of Homeland Security (DHS) is investigating the program.

Those who've been following related issues will recognize the "undermining" part from similar complaints about the 287g and (in Los Angeles) Special Order 40 programs. Those who use that line want (per them) law-abiding illegal aliens to remain here, but only want criminals deported. That's despite the fact that there would be fewer criminals overall if there were fewer "law-abiding" illegal aliens (many of those criminals prey on their non-criminal counterparts). And, it's despite the fact that we wouldn't have these problems in the first place without so many illegal aliens in the U.S. Those who use the line are enabling further illegal immigration.

The last I heard, the DHS IG was holding off on investigating Secure Communities until 2012, and as indicated at the link the investigation was being pushed by Rep. Zoe Lofgren, an immigration lawyer and strong supporter of illegal immigration.

Others coming out in support of Cuomo include Reps. Jose Serrano [2] and Nydia Velazquez [3] and Chung Wa Hong [4] of the New York Immigration Coalition. See the links for more on them.

Note that Serrano is all about the "community", by which he means Hispanics. In his tweet commending Cuomo [5], Serrano used the "latism" tag which indicates pan-Hispanic solidarity.

UPDATE: In an 80s flashback, I originally referred to "Mario Cuomo" as making the decision. In fact, his son Andrew Cuomo is NY's current governor and he's the one who suspended Secure Communities.

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[1] governor.ny.gov/press/06012011FederalSecureCommunitiesProgram

[2] Serrano says:

"Governor Cuomo has taken a brave and necessary step in suspending New York State's participation in the flawed 'Secure Communities' program, and he deserves great praise. He is firmly in line with our state's pro-immigrant tradition and on behalf of the immigrants and their friends in our community, I would like to thank him. Having New York State pull back from this unfair and aggressive program should be a wake-up call to the Department of Homeland Security. It is time to end this program and I am glad my home state will no longer take part."

[3] Velazquez says:

"I thank Governor Cuomo for showing the leadership and foresight to suspend this misguided program, which does not reflect New York's long history as a welcoming home for newly arrived immigrants. The Secure Communities initiative does not make our nation safer, but inhibits cooperation with law enforcement and violates immigrants' due process rights."

[4] Hong says:

"For centuries, families have gone to great lengths to come to this great nation, and we owe it to ourselves and our neighbors to make sure the law is on their side. Unfortunately, the Secure Communities program has failed to provide protections to many individuals. Governor Cuomo's decision to remove New York from the program is a right one, and we look forward to working with him to make our state safe for all residents."

[5] twitter dot com/RepJoseSerrano/status/76027297429327872