I’ve been in the Kindle world for a long time and mostly liking the distraction free nature of it, but also its integration with GoodReads (which Amazon owns or has heavy investment in), book insights, and ease of use across most any device I have. The biggest downside is community around the books and ability to actually use my highlights and notes easily. Also DRM lock-in drives me nuts as I have a ton of books in Kindle format that I picked up on the $ .99 to $3.99 sales (many time they are books I also physically own and I have different reading and use patterns for the formats, so having both has value for me).

Years back there was an utterly brilliant reader, ReadMill that not only had great reading experience, but its workflows and the use and reuse of highlights, notes and annotations was about as perfect as its gets. It also had a great reading community capability that got so much right that most do not grasp nor consider. I deeply miss it. It was purchased by Dropbox for the team and their good bye post brings a tear every time I read it – http://readmill.com