I just seeded a very large, perfect pomegranate using the method from last year's Food and Wine. Since we've had some discussion about this fruit lately, I thought I'd repost the directions for this neat trick. I got a cup and a half of seeds in 3 or 4 minutes. Here it is, in my own words:
Slice a bit off the blossom end, and score 6-8 cuts from the blossom end to the other end. Fill a bowl with water. Hold the pomegranate under the water and peel back the sections of peel where you made the cuts.
Do this all under water. When you can break the peeled pomegranate apart, begin loosening the white membrane and just nudge the seeds out of their segment with your thumb. All the seeds fall to the bottom of the bowl, the membrane and whatever peel that's left floats to the top. It's the niftiest thing you've ever seen. Drain. No fuss, no muss, just clean and glistening seeds to use however you choose.