On the heels of launching the first Pocket PC with GPS here in the United States, Mitac will release a business-oriented model, the $450 Mio 558. Though it lacks a GPS receiver, this model has a faster processor, more memory, and dual expansion slots. But the big story is the integration of both Wi-Fi and Bluetooth wireless networking.

Upside: The Mio 558 comes tricked out with all sorts of goodies. In addition to a speedy 400MHz Intel XScale PXA255 processor, the handheld has 64MB of RAM and 64MB of ROM, as well as CompactFlash and Secure Digital slots. We also like the user-replaceable battery.

Downside: While the Mio 558 supports Voice over IP, it doesn't come with the software to implement the technology. And though it doubles as an MP3 player, the device uses a mini (2.5mm) headphone jack instead of the standard 3.5mm, which means you'll need an adapter to accommodate standard 'phones.

Outlook: With its powerful processor and expansion capabilities, the Mio 558 will catch the eye of serious business users. But it faces stiff competition from power PDAs such as the HP iPaq H4350 and the Toshiba e805. Check back for our full review to see how the Mio 558 stacks up when it hits store shelves in April.