You already were happy to get the Samsung T509 on the US market from T-Mobile with a thickness of 9.8mm. Now Samsung makes that one look fat by introducing the SGH-X820 that only measures 6.9mm in thickness.

Update:
More Photos of the SGH-X820

Samsung introduced the new world's slimmest mobile phone at the ExpoComm 2006 in Moscow. The SGH-X820 is currently a GSM handset and features a 2MP camera and an MP3 player. The Samsung SGH-X820 hits China next month and is also slated to be released in Europe this summer.
More details in this Samsung press-release. Via AkihabaraNews, they also have a hi-res photo of the new slimmest mobile phone on the planet.