Information about the briefing has emerged privately from senior sources close to Sony at the Game Developers Conference in San Francisco, with several senior staffers from the firm's overseas offices making the trip to the event next week. However, further chatter among some developers at the show which pointed towards a rather more public PS3 unveiling in Tokyo later this month has been officially denied. Next week's briefing is believed to be strictly for internal staff at Sony, with even the company's closest development partners from overseas not on the guest list. Only the top Sony elite appear to have been invited. What exactly the Sony execs will get to see in Tokyo is hard to say. The final specification for the system is almost certainly complete, and if it is to be shown at E3, we'd expect that the physical design of the hardware has also been completed. However, whether software demonstrations will be a part of the briefing is another question entirely - but it seems eminently possible, with several well-informed sources at GDC insistent that several of Sony's Japanese partners have had quite advanced PS3 development kits for "a couple of months", with the kits now making their way into selected developers in the west as well.