The difference is that Redmond will likely attack the market through hardware partners like Hewlett-Packard and Acer, rather than introduce a Microsoft-branded device. Indeed, CEO Steve Ballmer demonstrated a prototype HP tablet powered by Windows 7 earlier this month at the Consumer Electronics Show in Las Vegas.
"It's almost as portable as a phone, and as powerful as a PC running Windows 7," Ballmer said at the time. "This emerging category of PCs really should take advantage of the touch and mobility capabilities of Windows 7," he said.
While Microsoft has not announced release dates or prices for tablet PCs, company executives have left little doubt that Windows-powered tablets are coming.
"We started with desktops and laptops, but we added notebooks, now we're adding tablets," said Microsoft Entertainment and Devices division president Robbie Bach, also speaking at CES. "At the high end you add all-in-ones, then you add game machines," said Bach.
"I think the tablet phenomenon is an opportunity," said Bach.
Microsoft may have a leg up in the tablet market in that its current OS, Windows 7, features built-in support for the touch screen capabilities that are mandatory on tablets, given their lack of keyboards and constrained screen real estate.
For its part, Apple is likely to use the same touch-screen OS software that powers the iPhone and iPod on its tablet.
Apple has scheduled a press conference in San Francisco Wednesday, during which it's expected CEO Steve Jobs will announce Apple's tablet. Whether the device is called iTablet, or some other moniker, remains to be seen.
Apple is slated to report quarterly earnings after markets close Monday. Apple shares were up 1.8%, to $201.30, in midday trading.