I've had access to an iPad through work for the past year, have had my Kindle-DX break, and am now using my Kindle Paperwhite regularly.
|Kindle Paperwhite - E-ink|
For books, though, I still like the Kindle (Paperwhite is my current version). It really is a different experience reading on the Kindle vs. iPad/tablets or PC/Laptops. The "feel" is much closer to books, and with a leather cover, is even closer.
Battery life for the e-readers is still astounding - maybe 10 or 20 times as long as a tablet, which means you are very rarely interrupted from a reading jag to plug in your device.
Years ago I sat through a motivational speaker (I think I wrote about this elsewhere on this blog) who's main point was authenticity - being "in" the events you are participating in. With respect to equipment, the dedicated e-readers are authentic - they are the digital equivalent of paper reading to a much higher degree than other devices. Other devices have much more generalized functionality (e.g. music, video, high end graphics etc.) but the e-readers represent the written page much better than the other competitors. They don't do much else - you may be able to access books on wifi and/or 3G, but the devices are really suited to surfing due to slow refresh rates and lack of color. You can e-mail books to yourself, or access your home e-libraries (thanks Calibre) which is an excellent advance. Most allow you to listen to MP3s, but this tends to drain the battery, so you lose as much as you gain.
|iPad - LCD|
I'm not advocating e-readers over iPads - both have a place, and the iPad is a much more functional tool - if you can only get one device, get a tablet. However, as e-readers drop in price, they become much easier to afford - if you like to read, get an e-reader.