From Scientific American:
An international team of scientists has discovered a massive new planet thanks to an effect described by Einstein 70 years ago. Microlensing–which occurs when a star crosses in front of another star and bends the light from the more distant star, magnifying it like a lens–predicted extra brightness for a red dwarf star roughly 9,000 light years from Earth. Based on the more than 1,000 images from the MDM Observatory in Arizona, team leader Andrew Gould of Ohio State University and his fellow astronomers calculate that this new planet has roughly 13 times the mass of Earth–making it about the size of Neptune–and orbits its star at about the distance of the asteroid belt in our own solar system.
More here.