As much as I love the physical book (for a lot of reasons, not least being that my father is a book artist), my favorite feature of the eBook is the searchability. It is incredibly frustrating trying to find that old quote from a hard copy when you're writing. eBooks therefore reduce the need to take notes, which is very desirable. I hate note taking while I'm reading. I don't find that it helps me remember more. I find it disruptive to my concentration.
Or selecting a word to define. Moby Dick had so much trade-specific terminology that it was actually frustrating to have to reference a dictionary or my laptop every time I came across a word I was not familiar with. Often times I'd just skip it and move on (Hey, I know it's a part of a ship. Good enough, right?). One evening I was on my couch and wanted to pick it up again but couldn't remember where I had left it. Instead of getting up to look for it, I just downloaded it to my iPad for free. Picked up where I left off and found that reading on the tablet was immeasurably more enjoyable than in paperback. It removed so much frustration. There are many books that are are served best by a corporeal form, but for me, I'd like most of them to be digital.