There is no Swiss Army knife for readers. The Kindle is, first and foremost, a text reader. The iPad is a color device for web access and, if you don't mind the small screen, a decent PDF reader. It is, for me, simply too heavy and uncomfortable to use for reading over any period of time. I am spoiled for internet access because I hate tiny, inadequate screens for PDF and web page displays and I simply cannot use the little toy keyboards on such devices. I know the current rage for iPads and such, but for me, there is no gap between my laptop and my Kindle to be filled with one.
I never use the browser in my K3 (I don't even know if it works or not) and I never use 3G because I have better tools for doing so. The K3 is near-perfect because of it's superior screen in normal reading light, its light weight (7.9 oz.), comfortable size, reasonable price, and its multiple-week recharge cycle.
