The quote provided from NASA Admin Charles Bolden, that "there are some areas that are better suited to commercial companies", is a reference to Bigelow Aerospace. Bigelow is building space stations, and their prototype was launched way back in 2006. A successor test unit followed in 2007, and it was also successful. This year (2015) Bigelow will launch the Bigelow Expandable Activity Module to dock with the ISS and add more interior room to space station for the first time in years.
Bigelow has bigger plans than selling add-ons to ISS too. Their BA 330 space habitat has (wait for it...) 330 cubic meters of internal volume. (You'll never guess the internal volume of their proposed BA 2100 module). For comparison the International Space Station 916 cubic meters of internal volume, but where the ISS took ten years and cost $150 Billion or more to build (or about $20 million per 1 person per 1 day), a BA 330 will go to orbit in a single rocket launch and Bigelow will lease space on it for prices starting at $25 million for two people for two months (a 120-fold cost improvement). (And I should note that Bigelow's lease rates are not its costs. Bigelow has spent decades developing this technology, and it needs to recoup that investment. Prices will only fall towards costs once competition appears. As long as Bigelow is the sole provider, expect them to make bank.)
Sidebar: Why hasn't Bigelow launched a BA 330 yet if they had working prototypes 10 years ago? Simply put, they mis-timed the market. Bigelow builds the stations, but not the rockets that get people to and from orbit. Bigelow thought that companies like Scaled Composites (that won the Ansari X Prize in 2004) would have reached orbit by now. Obviously that has not occurred, and if Bigelow wasn't shielded by the immense wealth of its billionaire founder, they'd probably be bankrupt by now. But luckily for them it seems that SpaceX's Dragon will be fit for crew soon, and Bigelow will finally have a mode of transport to orbit for its customers.Anyway, yeah, NASA won't be doing another ISS with Russian cooperation, not when an American company can lease them space station access for a tiny fraction of the cost. Both patriotism and financial prudence says that Bigelow is the near-term future for American's spending time in orbit. Whenever NASA decides the ISS cannot be maintained any further, it will be de-orbited and there will be no government-built successor.
Pictured Below: A rendering of several BA 330 modules connected by hubs. As pictured, this station would have more than twice the volume of the current ISS. There's no way to know if this particular configuration will be built, but it it were it would take about 4-5 months worth of SpaceX's launch manifest to put into orbit and cost 1% of what the ISS did.