I had an N800 and read quite a bit on it. If you really need/want the multifuntionality, go for the N800. However, I found that most of the time, I only read ebooks on my N800. I didn't notice any problems reading on the LCD screen, as some suggest. Being backlit, you can read in complete darkness. I used to get about 6-7 hours of reading time from a battery charge.
I now have a jetBook and I traded my N800 off. The reason is, I wanted a larger screen that showed more text. The jetBook's 20 hour reading time is a big plus. Although I don't often read more than 6-7 hours at a stretch, it is nice not having to plug the jetBook in all the time.
Now that New Egg has the jetBook for $170, that might sway your decision. I got mine when they had the coupon code promotion, and got the same price.
If you read my other comments about the jetBook, that may help you with your decision. I am satisfied with mine and like reading on it more than I did the N800.