If that happens, sales may take off. At least 50,000 tablet PCs were sold in the fourth quarter of 2002, research firm Gartner estimates. It predicts that this year about 425,000 will be sold, which would constitute about 1% of the mobile-device market. "Still, we're years away from seeing any significant movement of tablet PCs into the enterprise," says Ken Dulaney, Gartner's VP of mobile computing.

HP's Compaq TC1000 tablet features a 1-GHz Transmeta Crusoe processor.

Another key factor in the potential success of the tablet PC will be hardware design. Convertible models such as Acer's TravelMate C100, Hewlett-Packard's Compaq TC1000, and Toshiba's Portege series open like notebook PCs, then allow the monitor to swivel around and lie flat, which may appeal to sales professionals who need a device for giving product presentations. Another approach, a slate configuration that basically works as an electronic clipboard, may attract workers whose jobs require them to be in constant motion. Fujitsu's Stylistic ST4110, Motion Computing's M1200, and ViewSonic's V1100 use the slate configuration. NEC Corp. enters the tablet PC market this week with the launch of its Versa LitePad.

Still, as useful as various hardware designs might be, the number and variety of software applications will ultimately determine the value of tablet PCs. But developing applications for the hardware isn't easy. Most applications have been designed for use with a keyboard and mouse, Dulaney says. "Now they have to understand how a digital pen can be used and how their software has to be changed to accommodate this environment."

Windows XP Tablet PC Edition will help fuel acceptance of the new handheld computers because Microsoft included handwriting-recognition software in the operating system, says Tom Bernhard, director of strategic product planning for Fujitsu PC Corp. "Microsoft has also made it easier for software developers to write software for the tablet platform," Bernhard says.

Many of the tablet PC hardware vendors will fade away over the next year or two, predicts Gartner's Dulaney. Stalwarts Fujitsu, Hewlett-Packard, and Toshiba will survive based upon their size and reputation in the market. "A good tablet PC vendor will offer the services and software support that keep their customers' costs down over time," Dulaney says.

Smaller companies will have to partner with major vendors, such as Dell Computer or IBM, that don't have their own tablet PC offerings. Dell isn't likely to develop its own tablet PC until the market grows. And IBM is staying out of the market for now. The company phased out its TransNote tablet PC last year because few software developers designed applications for the product, resulting in slow sales.

	Motion Computing's M1200 can display an entire 8.5-by-11-inch form.

Fujitsu has positioned its Stylistic ST4110, priced at $2,698 with a wireless LAN, a tablet docking station, a 10.4-inch display, and an 800-MHz low-voltage mobile Pentium III processor, as an alternate to a desktop or laptop PC. The company acknowledges that tablet PCs will continue to appeal primarily to specific vertical markets for the next couple of years.

"The biggest change coming is that smaller organizations will be able to use tablet PCs because tablet solutions are getting less expensive and easier to deploy," Bernhard says. "You don't have to be an early adopter or a visionary anymore to use tablet PCs. You can buy an off-the-shelf application simply and inexpensively. It's the app that makes the hardware useable."