I have to say that so far the touch-pad Android reader scores highest, the Kindle second highest and the Nook lowest.
What I like about the Kindle?
Excellent screen and power control.
You can read text files.
Other than that it has a lot of the same problems as the Nook, slightly better but not a real solution.
You can't really convert PDF files into something readable. I have converted PDF files and I have read them on the Kindle and it really sucks. Maybe it is because most of the PDF files I use have a lot of graphs and images, micro-sections of materials, etc and I have a lousy converter.
Maybe that is the problem with the Nook too. Maybe they just need a good converter and a file format that handles graphics better.
In the end, I kept the Kindle for reading books I downloaded from the web in text format (www.gutenberg.org for example).
If you get a Kindle be aware that Amazon has deleted books purchased legitimately from Amazon off of some Kindles, You can read about it by searching "incest" and "Kindle" on Google. That scared the crap out of me because one of my favorite authors, Robert A. Heinlein, has an incest thread that runs through many of his books where one of the characters is in a plural marriage with his own mother. I avoided confrontation by purchasing the 802.11 version and never turning the wireless on. Maybe Amazon will turn it on remotely and delete my books anyway. If they do I will post that.
DRM is a big deal because a lot of nations don't recognize the same copyright protections that the United States does. Suppose I purchase a book in Pakistan, is the book deleted when I enter the United States? DRM is pretty screwed up.
In my opinion DRM and Copyright should last 20 years, the same as a patent. Screw all the rest of the greedy arguments.
I still use my XO OLPC laptop for reading PDF papers such as the scientific papers I read for work.
I would really like to try the I-pad sometime, I think it will stack-up favorably or even better to the Android touch-screen tablet.
Right now, in my opinion;
A "hard" book scores 2 out of 10
Nook scores 1 out of 10
Kindle scores 2 out of 10 (txt file capability :-)
Android scores 4 out of 10
XO-OLPC-1 scores 4 out of 10
Palm scores 2 out of 10 (M130, Tungsten W)
Blackberry scores 1 out of 10 (7100, 8320, 8330, 8900)
Normal laptop, windows or Linux scores 1 out of 10
Full size "tablet laptop" with folding screen scores 2 out of 10
I really want something in the 7-9 out of 10 range. So far nothing I have tried comes close to that range.
I really want something that:
Reads many different e-book formats
Reads PDF files without conversion no matter what they were published with
Does not crap out on files without DRM
Uses a generic (PGP style) DRM instead of credit card numbers (which always change)
Lasts at least as long as a Kindle
Uses a touch screen and does not get so nasty with finger prints
Is lightweight and small enough to easily carry
Won't break when you drop it a couple of times
Allows me to transfer reading rights of a DRM protected book
Stores books on a server
Won't delete books I have because the company hates the subject
Won't delete books because the company isn't sure I have rights to the book
Does not take the "guilty until proved innocent" DRM attitude of Microsoft, the RIAA and friends.
Reads TXT format books to me in various languages, translating on the fly (Yeah, I can dream... :-)
Has a full time *G connection to the internet
Can be used as a browser to read internet websites
Still looking for the "magic bullet" :-) I will write and post as I think about it to let anyone who cares know what I think about the various e-readers I try.