I am of a generation that is in transition. My older sister did all of here high school book reports and papers on a typewriter, while I did mine on an apple II (one of the few in my class). I have always thought electronic books would be the wave of the future, therefore really excited when the Kindle first came out.
I bought the first generation Kindle for my wife, and we never really used it. I bought the next generation 
So, it took me a while to get use to it. The final tipping point for me is the larger form factor of the DX. It puts enough information on the page that lets you spend more time reading and less time clicking "Next Page". The functions take a bit getting use to, like figuring out the difference between "Previous page" and "Back". Back being about going up a level.
I use the kindle as a daily source of the newspaper. I already have moved online for most news, but I like the ability to read material on the kindle. I find I read more of the articles compared to being on the web. The key feeds I like are WSJ, NY Times and Politico, though there are a few others (Blogs) that you can get. The kindle charges a small fee (basically air time) to get you certain blogs. Reading the WSJ and NY Times is a bit problematic - you need to switch between the "Sections" view which lists top level themes (World News, Technology, etc) and "Article List" which lists key articles. I do not think they publish all articles, but I have yet to resolve this.
I really like the notion of the pdf function. Essentially you register an email address for your kindle (i.e. energylover@kindle.com). There is an anti spam function to prevent abuse. You then email a pdf to your address and it shows up on the Kindle. The gray scale function on the kindle does not work real well here, but its sufficient for now.
I used the PDF function to download the entire The American Clean Energy and Security Act (ACES), (1,201 pages) and related amendments (300 pages), which gets me to the tree saving part. Its a bit ironic that a major bill on climate change results in so many pages. If they just fixed the margins the bill would be about 600 pages. But, I can say for sure, reading ACES bill on my kindle was easy and saved a lot of trees.
I need to figure out what the carbon foot print of my Kindle is (electronics etc), but I am fully bought into this technology now and in love with its potential. Its fun to get aa good book and turn it page by page, but I think I am making the transition to electronic permanent.
