I've been watching the next gen ereaders for a while, I like reading and I read a lot sometimes a book a day. I've never been that interested in eBooks partly due to the fact that I quite like dead tree books they never need charging and the display dots per inch is pretty good random access and the ability to display full colour pictures and even animation (flick books).
However as moving 6000 miles from home and having to get rid of most of my accumulated stacks of books has shown me they do take up a lot of space and are difficult to transport in any significant volume. Being able to take a library of stuff with me on a small electronic device (or even access said library remotely via the web) seems a good solution.
Out here in the US there are basically 3 main contenders for the eReader crown. The amazon Kindle, the Barnes and Noble Nook, and the Apple IPad. IPad is a realtively recent entry and somewhat less specialist than the others but it is positioning itself into this market with the IBooks feature.
Kindle and nook are the more seasoned veterans of the race and also dedicated devices they don't really do anything else. There is also currently a pricewar between the two with Kindle now at 189 bucks and Nook at 149 for wifi only or 199 for 3G.
The IPad for all it's flexibility is currently very expensive for a 3g model and you have to pay for the 3g on it, it just doesn't make sense. A lot of people have said the dedicated eReader market will eventually be subsumed into the IPad a like arena as more and more people try to cash in on the market. We shall see but for now the IPad is too damn expensive for my liking.
I like amazon as a store they have almost everything you could want and they deliver quickly this would seem to put me more in the Kindle camp. However I've been looking over the books for kindle and plenty of titles that I though looked interesting weren't available for it where as they were on the Nook which is a bit of a shame. Also the kindle's format is less open than the others used (although all of them deploy DRM of some fashion it's just easier to remove on the open format). Nook also offers things like the ability to lend books for a period and free hour's worth of browsing any book in the Barnes and Nobel Store which is nice. One of the things I like to do is browse the books in a store just look at titles of covers that look interesting pick out new authors or old ones that I've not looked at in a while it's something I would often do when away on business since books don't require any of the other paraphernalia that games or dvd do, though the nearest B&N is not that close to where I am so how often I would be able to make use of this feature is questionable.
Both the kindle and the nook use 3g to get their books, there is no fee for this it's free. The Kindle offers world wide 3g where as the nook is US only. This is an interesting feature seeing as I may well be back in the UK at some point. However the Nook has the option of Wifi which would probably be just as accessible as 3g in most places you would want it.
Design wise the Kindle looks like something out of the 1970's all buttons all over the thing plastic casing black and white screen (admittedly very nice eInk screen but it looks old), the Nook has a cleaner look with its touch screen controls which also adds a splash of colour at the expense of less battery life.
I think the current clincher in a very close race between the two devices is the extent of their libraries. When searching for books I could find almost everything I wanted on the Nook where as kindle had loads of stuff that just wasn't available. I found one reverse case (the book Pete recommended) but it was very much a winner for the Nook. The other thing is I know the format of the Nook books is open that means when the Nook is a thing reserved for a museum there is a good chance there will be someone somewhere that's written a converter to what ever holographic space tablet is the new wonder device.