Rob Bushway, owner of Zoe Technologies, a firm specializing in web development and technology consulting, who also runs TabletBible.Com for inkable bibles and books for Tablet PCs has posted this on his blog:

I have no less than 5 sources saying an Apple Tablet announcement is due soon… And the Intel talks are for battery saving Sonoma-like Powerbook and Tablet tech, I’d heard this 3-4 weeks ago from 3 sources… And it exists, honest, [have] seen a prototype. Instant On, running a reduced version of OSX, with some funky start-up PDA like Apple icon menu. Touch only (white touch pen), [at] least the version I saw.

Full article here.

Related MacDailyNews articles:
Apple granted U.S. patent for Tablet Mac (with images) – May 10, 2005
Apple looking to add wireless connectivity to iPod, rumored Tablet Mac? – August 25, 2004
Apple hints at ‘handheld tablet computer’ with European design trademark filing – August 13, 2004
The Age ponders video Bluetooth iPod; tablet Mac possibilities – January 22, 2003
Apple readying secret iTablet for Macworld unveiling? – January 03, 2003
Tablet Mac watch begins – November 17, 2002