Have you ever wondered what iPhone apps are hot in Japan? If you're attending this year's MacWorld conference in San Francisco, you'll have a chance to find out. There, Nobuyuki Hayashi, a Japanese Mac and iPhone tech journalist and blogger, is hosting an event called "Japan iPhone Apps: State of the Market," which will be held on Wednesday, Jan 7th. If you can't make the event, here's a sneak preview of the apps being featured.