New technique for discovering dark, dwarf galaxies

At my alma mater, UIUC, researchers have discovered a dwarf galaxy some 4 billion light years away from earth, which emits little, if any, visible light, by using gravitational lensing of a even more distant galaxy that is 'behind' the dwarf galaxy. This technique, they think, will allow for more dwarf galaxy discoveries, and also allow astronomers to test dark matter models, which these galaxies should fall under since they are not in the visible part of the spectrum. dark matter is, of course, one of THE open questions in all of physics, and perhaps this new technique can shed some new light on the topic. (ouch, I know this pun is painful..I'm just not bright enough to come up with any others...)