Would an antimatter apple fall up?

Shaun Saunders sends in an article with some real meat on it! An article in New Scientist online ask the seemingly innocent question: How would antimatter react in a gravity field? As the article points out: Physicists have studied antimatter, the mirror version of ordinary matter, for decades. They know, for example, that antiparticles have the same mass as ordinary particles, but opposite charge. But no one knows what effect gravity will have on such particles.

Now several groups want to measure exactly how the Earth will pull on antimatter. The tests would create a horizontal beam of anti-particles and measure how much gravity deflects it.

The test may show no difference between the way matter and antimatter fall. But some researhers are holding out hope that they may see something completely unexpected, which could point the way to new gravity-like forces, or perhaps even anti-gravity.