Microsoft believes portable Tablet PC devices will be outselling desktop PCs within a few years, but will there really be any demand from corporate users?

Executives from Microsoft and its partners were promoting the firm's Tablet PC specification at the Comdex IT show in Las Vegas earlier this month, and said it would be the mobile business PC format of the future.The portable devices will run Windows XP and will use a stylus for input. Microsoft chairman Bill Gates said he expected the Tablet to become the most popular form of PC within five years.

But apart from a lot of hype and a few demonstration prototypes, there were few details regarding potential products, features, costs and availability, despite the fact that Microsoft lined up an array of partners including Compaq, Acer and Fujitsu.

Prototypes on view included a convertible design that is both a laptop and Tablet PC, an A4-sized Tablet, and a small design closer to a PDA or mini-notebook.

Ted Clark, vice president of the Tablet PC group at Compaq, was tight-lipped on his company's plans to build devices based on the specification. 'We are just at the prototype stage and are evaluating many design possibilities,' he said. 'I don't expect we'll announce our product line-up much before the middle of next year.'

Clark said Compaq's Tablet PCs would probably be slightly more expensive than comparably equipped notebooks. 'I expect the Tablet will probably cost more,' he said. He added that eventually there couldbe a range of Tablet designs, varying in price depending on their functionality. Clark said he did not expect the Tablet PC to have much effect on demand for PDAs, but predicted that it will replace some categories of laptops.

Leland Rockoff, a director in the Microsoft Tablet PC division, said that he expected most early demand for the Tablet to come from users who now use ultraportable PCs. 'Users of those really slim, lightweight machines will probably be the first to migrate to the Tablet PC in any meaningful way in the first year,' he said.

Rockoff said that the first products are set to ship in the second half of next year. He added that Microsoft is dictating 'as little as we possibly can' to hardware partners regarding the design of Tablet PCs and has publicly posted the hardware requirements.

The Tablet PCs will be able to run the same applications as desktops with Windows XP, said Rockoff. Microsoft wants to ensure that the Tablet is not seen as a niche system that requires special applications to be ported or developed, Rockoff explained.

However, some observers have questioned whether there will be much demand for such devices. Dell chairman Michael Dell compared the Tablet PC to previous pen-based systems, such as those based on Windows for Pen Computing, a previous Microsoft attempt to promote a stylus-driven platform. 'Go back to the pen PC phenomenon about 10 years ago. Where were all those customers for the pen PC when it was finally introduced?' Dell asked.

Jeff Raikes, group vice president of Microsoft's business productivity group, argued that the Tablet PC is a natural step forward from notebook designs. 'Our research has shown that a laptop doesn't get used for the bulk of most people's daily work because it is not that portable or easy to use,' he commented. 'With the Tablet PC, users get the full power of Windows XP and a lightweight, portable system with built-in wireless support and the ability to take notes as they would with ink.'

Raikes also announced a number of new hardware manufacturers for Tablet PCs, including NEC and ViewSonic. Software developers include Adobe, Corel, Groove Networks, LexisNexis and Zinio Systems, while chips are being supplied by Intel, Transmeta and VIA Technologies.

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