Are Apple and Microsoft playing PR games -- or trying to psych each other out -- with dueling leaks about their upcoming tablet devices?

The latest round in the whisper campaign told blogger Mary Jo Foley that Microsoft's "Courier" tablet runs Windows 7, builds on the OneNote concept, rectifies shortcomings of TabletPC apps and may be built and sold by Microsoft in mid-2010.

She's following up on the original Courier leak to Gizmodo.

With Microsoft getting some mindshare for its tablet, whispers about Apple's new tablet began appearing today.

The iLounge blog has a really tantalizing batch of details about the device, which now has a 10.7-inch diameter screen, runs the iPhone OS and will be available in early 2010 with and without 3G wireless service. It's not a netbook or productivity tool as much as a media tablet, bringing apps and Apple services to a larger device.

Both sound like major challengers to the Kindle and other e-books, if they can keep the prices reasonable.

If the rumors are to be believed.