As best I can tell, Obama's proposed reforms to current security practices are mostly window dressing. He has said nothing at all about the NSA's practice of deliberately sabotaging widely used encryption software, its massive interception of text messages, or most of the rest of what it is doing and, arguably, should not be. His main proposal is to maintain a pen register on the entire U.S. population—a record of what number called what number when—while moving it one step further from direct control by the NSA.
This raises an obvious question: why? I can see three plausible answers. Starting with the one most favorable to Obama and ending with the one least favorable:
1. He really believes that the activities of the NSA help protect America from terrorists and that any significant restriction would reduce its ability to do so.
2. He believes that restricting the NSA will make him and his party appear weak on national security issues, losing him votes on the political center, and that the people who would approve of his doing so are for the most part already Democrats.
3. He regards the ability of the government to collect massive amounts of information on ordinary citizens as potentially useful for reasons that have nothing to do with terrorism—in the extreme, as a way of making it possible to blackmail politicians into supporting his policies or damage political opponents by leaking information about their sexual or other misdeeds to friendly media. In a less extreme version, as a way of identifying and prosecuting people who leak information unfavorable to his administration.
If I had to guess, my guess would be number 2, but I am not willing to rule out either of the other alternatives.