The most important news at today’s presser was Obama’s announcement that he will embrace what may well shape up to be serious reform of the current system of oversight — or lack thereof — as to the NSA surveillance programs that have consumed so much attention.

This is welcome. The question remains how deep it will go, and how aggressively Congress will press to ensure that reform is meaningful.

Obama said he’d work with Congress on proposals that would provide for an advocate on behalf of privacy rights to defend the public’s interest when the government asks the secret Foreign Intelligence Surveillance Court for authorization of surveillance. He said he would create a panel of civil liberties advocates and former intelligence officials to look at ways to tighten up Section 215 of the Patriot Act, which gives the government the surveillance authority it claims. And he said the Justice Department would release an analysis of the legal rationale for the programs.

“It’s important that the president himself is now engaged on this set of issues,” Jameel Jaffer, a senior civil liberties attorney with the ACLU, told me. “We appreciate that. We think it’s overdue. But still, it’s good that he’s engaged.”

Jaffer notes that it looks as if reforms are likely to focus on the back end of what is done with the data collected, rather than the front end. That is to say, reform will likely address what can be done with the data, rather than what data can be collected. That is important, but it will probably not satisfy civil libertarians, who have a problem with the data collection itself.

“If they were intending to make changes to the scope of the collection, I think they would have said that clearly, and they didn’t,” Jaffer told me. “They are proposing to be more restrictive as to what they do with what they collect, but I didn’t hear anyone say they were going collect less information.”

Indeed, Obama’s assertion today that he doesn’t believe the programs constitute a threat to civil liberties — but that he understands the need to take steps to restore public confidence in that — suggest “front end” reform may be unlikely.

The promise of more transparency — as well as of public representation before the FISA court — is a welcome step. It remains to be seen what the transparency will look like — as Jaffer notes, it doesn’t appear to constitute the releasing of the FISA court opinions themselves, which some members of Congress and civil libertarians have been clamoring for. But Obama’s promise to act, and his admission that the current oversight is inadequate — and that he had erred in assuming it would be — are welcome.

Indeed, today’s movement should serve as a reminder that public pressure can force action, at least of a sort. It’s unlikely that we’d be here if Edward Snowden hadn’t come along — Obama himself allowed that Snowden had at a minimum hastened the process — and the continuing efforts by members of Congress to chip away at the NSA surveillance monolith clearly had an impact over time.

However, whether this ends up amounting to meaningful change remains to be seen — and this is something that is also up to Congress, and to the public. The recent House vote on an amendment to end the bulk metadata program — which came very close to passing — suggests there’s broad consensus in Congress for real changes to the scope of data collection, which is to say, changes to the programs themselves. On the other hand, there is a good deal of establishment support for the programs, the power of which can’t be dismissed. At a minimum, Congress should be able to ensure that reform of the oversight and transparency around these programs is far reaching and serious.

It’s good that Obama has engaged. But Congress needs to step up and help ensure that this engagement results in something meaningful. “You’re never going to have an administration tie its own hands,” Jaffer says. “It’s clear Congress has a responsibility to act.”

Greg Sargent writes The Plum Line blog, a reported opinion blog with a liberal slant -- what you might call “opinionated reporting” from the left.