The eyes of a million teenagers will be looking towards Los Angeles this week as two of the most anticipated product launches in the game industry this year take place at the Electronic Entertainment Expo (E3).

The show, which begins on Tuesday, will see Nintendo unveil the successor to its popular and market-leading GameBoy handheld gaming device and Sony launch its assault on Nintendo's lead with the unveiling of its PSP handheld device.

The launches are anxiously awaited by many, partly because the coming battle between the two companies is likely to characterise the year-end selling period and partly because relatively little is known about the devices.

Sony first disclosed plans for its handheld device, the PSP, at E3 last year and has since released a string of preliminary specifications and a design prototype image.

According to those preliminary specifications, it will have a 4.5in, wide-screen TFT LCD with a resolution of 480x272 pixels, 3D graphics, support for MPEG4 video and a USB 2.0 port.

Sony also said the player will use a new media format called UMD, or Universal Media Disc. The 60mm optical discs will be encased in a cartridge and hold up to 1.8GB of data.

Later in the year the company said it would ship the PSP worldwide during the year-end holiday season however that schedule has subsequently slipped. In February this year Sony said it would only ship in Japan during 2004 and see release in other markets in 2005.

If little information is known about the PSP, even less is known about Nintendo's DS device. The Kyoto-based company disclosed its work on a new platform in January this year and revealed nothing but a few technical details.