I have a Kobo Clara and love it! It has really good battery life, and you can just drag/drop epub files straight from your computer, it's compatible with Overdrive, and it has it's own bookstore (I'm not familiar with it though). For me the biggest benefit is the setting to invert the colour of the screen, it makes reading in the dark just before falling asleep a lot nicer.

They just came out with a second generation of that model as well, just the usual incremental upgrade you expect with tech products these days.