last year I had the same dilemma as you have, I tried several options and I settled for the Clevo TN70M. This is 7" tablet with a keyboard with a tilt screen like the ASUS Eee T91. Since then I never use the N800.
The possibility of using the device as a Netbook (using the keyboard) and as a tablet is amazing, since there are times I need to write a lot (e.g. on train) and i use it as a netbook using the keyboard, and when I am browsing the net, reading the RSS feeds, etc, I close it as a tablet and it is more practical.
The device has the mouse pad and buttons on the side of the screen and this is key to be usable it as a tablet, since it makes live easier using any application.

If I could make a small change would be to have a 9" display. The one I have with 7" (set at 800x600) although it supports 1024x768 but it is difficult to read small text with the higher resolution on the 7" display.
I hardly us the laptop I have at work, since with this device I can do everything, and even use it to do my presentations (has a VGA port). Weights less than 1Kg and fits in my small bag. Runs for 5 hours on batteries.
I would recommend something similar. You can install Ubuntu or Windows. There are newer models on the market now.