The picture in question has hit its "viral" stage popularity, and considering the people in it, as well as the subject matter, it only makes sense. It's not often we get to see the Leader of the Free World and the best communications officer in the galaxy together, sending a message of peace and prosperity. Clearly, the planets have aligned, bringing us the following gem:
Click for larger image
With President Obama is Nichelle Nichols, otherwise known as the original Lieutenant Uhura (sorry, Zoe, but Nichelle still rules), and they are offering the universal sign for goodwill and long life, made popular by the Vulcan race, most notably, Commander Spock.
The image was posted on Nichols' twitpic page, and while it was taken at the end of February, the image was posted 14 hours ago. At this point, the image has already amassed close to 200,000 views. None of her other images have eclipsed the 10,000 views plateau, which is great indication of the image's viral popularity.
Considering the fallout after Obama slashed NASA's budget, he clearly needs all the intergalactic assistance he can find. Good thing for him, Lt. Uhura was willing to comply.
In light of the image, it's hard not wonder what Obama's approval rate is among Star Trek fans.