Microsoft Corp. (Nasdaq: MSFT) and its partners made a big splash with last week's new "ultra mobile PC" products, but research firm Gartner Inc. says the units aren't quite ready for the big leagues.

The UMPC is a slimmed-down version of Microsoft's Tablet PC. The device runs Windows XP, supports Bluetooth and WiFi, and weighs less than two pounds with its 7-inch screen. Prices are expected to range between $500 and $1,000, depending on capabilities, and the first offerings should be out next month. (See Microsoft Goes 'Ultra Mobile'.)Gartner, however, says users -- particularly enterprise users -- should hold off before rushing out to buy these new "tweener" gadgets that are neither laptop nor PDA.

"The UMPC concept has promise, [but] today's hardware cannot deliver on it," say the researchers.

In fact, enterprise users should "wait for more mature UMPCs -- and low-cost content services -- to emerge before considering them for field sales or other 'notebook replacement' applications."

As it stands, the devices are said to have too short a battery life -- enterprise users should look for at least eight hours -- and cost too much. Gartner suggests that $400 or below is the ideal price point to be anything more than "proof of concept" devices.

In general, enterprise users seem to have been put off the UMPC's forbears, the Tablet PCs, because they couldn't get used to the touch-screen interface, and Gartner suggests that improvements need to be made there, too.

In fact, the firm has a harsh kiss-off for Redmond and Intel Corp. (Nasdaq: INTC), the two companies with the most behind the UMPC concept: "The UMPC as currently conceived will fail to achieve mainstream success -- defined as unit sales in the millions rather than the thousands -- by 2009."

Ouch!

— Dan Jones, Site Editor, Unstrung