"NASA Learning Technologies (LT) project supports the development of projects that deliver NASA content through innovative applications of technologies to enhance education in the areas of science, technology, engineering and mathematics (STEM)." Source (http://ipp.gsfc.nasa.gov/mmo/).
This is some great news that NASA will be following the steps for online learning through an online platform such as a MMO game engine. Many organizations have tried to use virtual worlds like Second Life or There world builder but the learning curve is very high for some users. Also the lack of standards makes virtual worlds a unique platform.
What if you could link all virtual worlds together - like travelling to another world seemingly. Ultimately you will have one BIG world with many branches to other worlds - like the Internet. You could as an avatar start from NASA MMO and "travel" to Second Life islands and other MMO games like World of Warcraft.
In any case MMO made by NASA will be beneficial to students of all ages exploring our known universe while being in your chair. I do not think we will be able to see our solar system any time soon from our own eyes in space ships. But a virtual world or MMO type of platform will be a great jump (safely) into space exploration. (I am off to Saturn on a quest to explore its moon, need to deliver a message - 500 experience worth )