So, this is the first I've heard on the actual types of nuclear reactors approved by President Obama and I must say, I'm a little disappointed. The two most important factors affecting public perception of nuclear reactors are reactor safety (i.e., risk of meltdown or fire) and waste disposal. Apparently, this was lost on the Obama Administration and his energy advisors:

On February 16, President Barack Obama announced loan guarantees totaling more than $8 billion for two new light-water reactors in Georgia, part of an initiative to restart the nuclear power industry in the U.S.
Light-water reactors are today the most prevalent type of reactors, prone to costly minor malfunctions and overheating. If somehow there is a leak in the cooling water system, the reactor overheats and you have the potential for fire (see Chernobyl) or total meltdown. In the US, total meltdowns are practically impossible and we have containment units in place in the event of a fire.

However, even if there are no resulting deaths or citizen exposures to radiation, such a catastrophe would be a public relations disaster. The clean-up costs would be astronomical and you can bet that the nuclear program would come to an end.

There are alternatives to light-water reactors.

The most prevalent type of fast-neutron reactor, so-called because the neutrons used to initiate the fission chain reaction are traveling faster than neutrons moderated by water in conventional nuclear reactors, operate at temperatures as high as 550 degrees Celsius and use liquid sodium instead of water as a coolant. Sodium burns explosively when exposed to either air or water, necessitating elaborate safety controls. Nevertheless, as far back as 1951 at Idaho National Laboratory, such a sodium-cooled fast-neutron reactor produced electricity.

But attempts to make that technology commercial have largely failed, mostly because of difficulties with controlling sodium fires and the steam generators that transfer heat from the sodium to water. Japan's Monju sodium-cooled fast neutron reactor caught fire in 1995—and has just received permission to resume operation this month after years of technical difficulties in repairing it, along with legal challenges to its restart.
Sodium cooled "fast breeder" reactors greatly reduce the total output of nuclear waste, but if you've ever taken a chemistry course, you've witnessed the combustibility of sodium. These fires are extremely difficult to contain. And since these reactors operate at a higher temperature, there is the resulting increased risk of meltdown or fire.

So what about the travelling wave reactor?

The proposed technology would employ cores that, starting with enriched uranium, fission over at least 30 years. The cores could theoretically also employ the depleted uranium from existing reactors, as well, thus consuming some of the nuclear waste problem, explains nuclear engineer John Gilleland, president of TerraPower, in a video demonstration
Imagine a huge cigar, filled with fissionable material and lit from one end. The slow burning nuclear reaction could last up to 60 years. I feel this type of reactor holds promise, but the technology is to date completely untested. I don't believe there are even any plans to begin construction on a prototype facility. Count this out, for now.

Then there's my favorite: Pebble Bed Reactors

The pebble bed reactor (PBR) is a graphite-moderated, gas-cooled, nuclear reactor.

...

This type of reactor is also unique because its passive safety removes the need for redundant, active safety systems. Because the reactor is designed to handle high temperatures, it can cool by natural circulation and still remain intact in accident scenarios, which may raise the temperature of the reactor to 1600°C. Because of its design, its high temperatures allow higher thermal efficiencies than possible in traditional nuclear power plants (up to 50%) and has the additional advantage that the gases do not dissolve contaminants or absorb neutrons as water does, so the core has less in the way of radioactive fluids. A number of prototypes have been built. Active development is ongoing in South Africa as the PBMR design, and in China whose HTR-10 is the only prototype currently operating.
The major problem with PBRs is waste. They greatly increase the amount of nuclear waste, though it is not nearly as radioactive as from a light-water reactor. However, the only chance for a nuclear disaster is from an external explosion, such as a terrorist attack.

So anyway, those are the most prevalent options for nuclear energy. Feel free to add your two cents.

Here is the link for the previously quoted Scientific American article:

Are New Types of Reactors Needed for the U.S. Nuclear Renaissance?: Scientific American