The only issue I have with e-readers versus paper books is that of formats. Different companies and models support different file formats and apply different Digital Rights Management systems in ways that can make the purchase and reading of books from different websites frustrating. For example Kindle (Amazon.ca) cannot read EPub which is widely used by libraries and due to the proprietary file system ebooks purchased at Amazon.ca cannot be read on other readers.
I am not a fan of Digital Rights Management or restricting things through proprietary formats. I prefer the open source philosophy which is modeled on the humanitarian scientific tradition of shared knowledge and seems to better reflect the Spirit of God’s Grace. However, practically speaking, the few theological titles that are available are mostly available through Amazon so in a few months I will be supplimenting my Sony TR – 2 with a very basic Kindle model, just so I can cut down on the amount of paper I haul around continents as I move around.