My bag has both a laptop/tablet and a Sony ereader. It may seem silly but they really do serve two different needs. Like it was mentioned earlier, the tablet can read anything you throw at it since it is a working computer. I use it to quickly overscan documents, download new ones, clean up and convert formats as well as normal day to day computer tasks like email, surfing and TV.

So why carry a reader? Because its faster, lighter and can be read easily in more environments. While the computer does more I actually read more on the ereader since it's up and running in a couple seconds as opposed to several minutes. It holds everything I'm reading currently or planning to in the future and in an easily used form (light to hold, easy to handle like most eink devices).

So is ANY reading done on the tablet? Sure! Large PDFs, searchable tech documents, articles and reports with detail graphics, all these are still (generally) better with a large color screen with a little horsepower and an instant screen refresh behind it. Occasionally I want to read something that is DRM locked out the wazoo and usually that will also require a computer to do (though it looks like the Iliad ereader has that licked for the Mobipocket DRM side).

So basically the ereader is faster, lighter and easier to handle with a better reading time between charges while the tablet is more compatible with every format, easier for viewing detailed drawings and PDFs, and much faster for document searching and reference work.

(These results are not typical. See your doctor before starting any reading plan.)