The Ultra-Mobile PC (UMPC) is a revolutionary new type of device that fills a gap in the market between PDAs and full-blown Windows laptops. Alternatively, it is an underpowered Tablet PC with a desperately short battery life – take your pick.

Reaction was swift after Microsoft unveiled the new design at Cebit in Hanover this month. Much of the comment was negative, which can probably be blamed on reality not quite living up to the hype and speculation that preceded the announcement.

Whether the platform’s blessing by Intel and Microsoft will lead to widespread adoption of UMPC devices remains to be seen. It is true that the first models are very similar to Tablet PCs, and this has caused some analysts to dismiss them because of the low take-up of the Tablet PC itself.

There is some merit in this argument. Last year, Motion Computing launched a mini Tablet PC that is virtually indistinguishable from the UMPC specifications. Called the LS800, this device weighs less than a kilogram, has an 8.4in display, runs XP Tablet PC Edition, and is based on the same 1.2GHz Pentium M chip as Samung’s Q1 UMPC.

The devil, as ever, is in the detail. Motion has put a lot of development effort into making sure its Tablets are evenly balanced for handheld use, and the display can be clearly read in a variety of lighting conditions. The LS800 also has corporate-friendly features such as a fingerprint scanner and a Trusted Platform Module (TPM) security chip.

Contrast this with Samsung’s Q1, which has an “instant AVS multimedia feature” to let users view movies, photos and play music without having to boot Windows, plus a three-button pad to play games. Clearly, Microsoft and its hardware partners can’t decide whether the UMPC is a business client or a consumer gadget.

If firms really are clamouring for a more mobile style of PC, the LS800 looks more suitable than these early UMPC models. Yet Motion Computing is the first to admit that its products are aimed at industry-specific applications in fields such as healthcare, education and engineering.

This isn’t to say that there is no market for an ultra-compact Windows PC; OQO has shown there is one with its PDA-size Model 01, but high cost always seems to be a downside of such specialised miniature devices, as does short battery life.

With this in mind, Intel and Microsoft could perhaps have been a little more ambitious. For example, the UMPC could have had new mobile chips designed especially for ultra-compact devices, rather than using off-the-shelf laptop chips.

Microsoft could also have based the operating system on Windows XP Embedded instead of Tablet PC Edition, which would have enabled devices to do without a battery-draining hard disk.

But what we have now is just version 1.0 of the UMPC platform. As with many other Microsoft projects, the concept is likely to be refined and upgraded until it meets user requirements. Perhaps by the time UMPC version 3.0 ships, it will be a useful product that fulfils a clearly-defined business need.