I want one too!!
I think which one you want depends on where you plan to be reading and how often.
I have only got experience of two and i know which one I want:
I have used my other halfs ipad for reading and it is pretty decent - especially because you can read at night without any extra peripherals to light it up. However it gets heavy after a while and is not so comfortable with one hand. Oh and the battery life is not that good.
Kindle on the other hand is awesome. My Mum has one and loves it. I have used a friends Kindle Keyboard and it is really nice. It is light to hold, the battery lasts for weeks (!) which is great for holidays.
We took the ipad on holiday and it is a bit of a pain having to remember to always put it on charge, also it certainly makes you bag feel a lot heavier especially once you have been out for a while.
The kindles can be pretty cheap - I am very tempted to get one. The only thing putting me off is that there are no service centres in China if it breaks. You on the other hand don't have that problem!
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