@ Steven Knox and M.White
After a long period of cynicism about e-book readers and being happy to read e-books on my netbook and laptop, I took the plunge and bought a Sony PRS-505 for £150 in the UK. I find it to be amazingly good for what it is and what it cost me.
I can find faults with it as I can with everything but they are 'chasing after perfection' things that can be adapted to.
As an example, the screen appearance (purely when reading, when it is in front of you) is nowhere near as good as my 15" laptop using the Mobipocket reader application which gives me a high contrast b/w page with smooth scroll and enormous adjustment of font and text size. But then again, can a paperback book do that? (Clue:- no, but the Sony reader can adjust font to three different sizes) Can I carry my laptop in my pocket and easily use it on a train?.........etc
You can do lots of nitpicking of that nature on the ergonomics but it's all nitpicking. For the first time in many years I've read a book in bed using the Sony reader and it is small/light/convenient enough to do that.
I find that the battery lasts for 2 weeks with my medium usage even with me sending it into sleep mode (not turning it off) so that it starts up at the same page I was last reading. I've got 140 free books on it (100 included free with the purchase) and have room for hundreds more.
Also, I can make my own .pdf e-books, including pictures/diagrams and transfer them to the Sony reader (for detailed, colour tinted maps, the results are not good but with a suitable image, it looks very good). It's very flexible and very usable - I've become a fan, i admit it.
I download non-DRM e-books at home on my computer then do a simple transfer to the reader, I'm working my way through all the out-of-copyright classics that I didn't read when I was younger. The issue of wireless phone links is a big one and I think is the way that the manufacturers want to get themselves latched onto many little income streams in the future. Personally I would not want to be the teat that they suck on and am happy to use my laptop at home or my netbook/3G-dongle to download and transfer reading material for the reader (simple USB cable link that also does device charging).
If you like reading books away from home, the e-book readers are very good for the job. If you want to download content onto an e-book directly then I don't think the market and services are mature enough to be worth trying. Maybe one day there will be an e-book that you can put a SIM card into but it will be expensive since it wont give guaranteed income stream to the manufacturer.
If you 'know' computers and the internet (the mass market do not), you can have a very usable and flexible reader right now with lots of content to try and buy (or get free stuff easily).
The second hand prices on e-bay for the Sony PRS-505 are very high so you can get one there and resell it if you don't like it.