Personally I feel that Nokia has made bigger (a lot bigger) mistakes than this potentially planned "tablet" idea, but...

if the device will be:

• Only ipad-sized model avilable (i.e. still no pocketable models) and - knowing Nokia - thicker
• Only uses Meego-partner Intel's x86 platform rather than ARM
• Priced similarly to N900 (i.e. higher than competing devices in the Android ecosystem)

then Nokia has more issues to deal with than simply being late to the market they actually helped create with Maemo and 770/N800/N810 a few years ago.