President Barack Obama has said he wants to shut down the telephone surveillance program that has been the subject of intense controversy since it was revealed in top-secret documents published last summer. The US government will stop maintaining its database of telephone call "metadata," which includes all numbers dialed in the US as well as their duration and other data.

"Earlier this year, I announced a transition that would end the Section 215 bulk telephony metadata program as it previously existed and that we would establish a mechanism to preserve the capabilities we need without the government holding this bulk metadata," Obama said in a statement today. "I did so to give the public greater confidence that their privacy is appropriately protected, while maintaining the tools our intelligence and law enforcement agencies need to keep us safe."

A fact sheet lays out the details of the changes, and they are significant. The data itself will still exist in the hands of the phone companies, as it always has (it's the same data on your telephone bill), but it can only be queried when the Foreign Intelligence Surveillance Court (FISC) approves requests for specific numbers. That's the difference between the government going to a judge and saying "We'd like to see the metadata for 555-123-4567 and all of his/her contacts" and the government already having all those contacts in its own database with no supervision for individual searches.

The queries will also be limited to "two hops" out rather than three hops. As Ars editor Sean Gallagher explained last year, the "three hops" limit isn't much of a limit at all . And the "two hop" limit means intelligence agencies will still be able to get all the contacts of all the contacts of suspected persons. That might not be the whole country, but it's a lot of people.

The idea of taking the phone database out of the hands of the government and leaving it with the phone companies was one of the key recommendations of the surveillance review panel convened by Obama.

There are still a few reasons for concern, however. First, there is still no public advocate at the FISC, as reformers have recommended. As long as it's a one-sided, secret process, there's still a risk of FISC being essentially a rubber-stamp court. There is also hedging language in the president's proposal, stating that queries must go through a judge "absent an emergency situation." Finally, if the actual searching is going to be done by the telephone companies and not by the NSA, there are real questions about how that could be done in a way that is effective, safe, and subject to real oversight.

In order for these proposals to take effect, Congress will have to pass legislation. In the meantime, the Department of Justice will be asking for re-authorization of the program with "substantial modifications." There are already competing surveillance bills in Congress; some would shut down the program completely, while others would allow the intel agencies more leniency than Obama would. According to the New York Times, a draft bill now being talked about in the House would require the NSA to submit specific subpoenas, but without judicial approval.

Despite all those caveats, the president's admission that the database needs to end in its current form still seems like a watershed moment. Obama's first responses to criticisms about surveillance were defensive. In early press conferences , he defended the integrity of the people working for US intelligence agencies and condemned the Snowden leaks as both damaging and the product of "sensational" press coverage.

Over time, though, the continued revelations of spying on allies, enemies, and Americans alike have made some elements of US spying appear out of control even to the staunchest surveillance hawks. There has been a sea change in the politics of this issue over the last year. In some ways, even after almost a year of steady revelations, the massive phone database still seems to be the most stunning and troubling of all that was revealed. Today, 10 months after it hit the front page of newspapers worldwide, without support from the president and with dwindling support in Congress, the "bulk telephony metadata" seems like it really is headed for the dustbin.