I use both: ebook readers and hardbacks.
You see, I'm a book collector, someone who enjoys the feel and smell of a book - that sense of something beautiful held in my hands.
An ebook reader, however, is now my main source of reading. It's allowed me to experiment on some of the most ludicrous, maniacally egocentric, child-like indy writers and writings imaginable (what can I say: I'm a masochist), while also indulging in my love for works of Literature.
The wonder of it is that sometimes - sometimes, mind you - I actually find a piece of indy writing that aspires to the best of the genre fiction out there. Even when they're horrible (the writing - not the writers), it's still lots of fun.
I read great works of Literature for the insights into human nature; I read genre fiction for the chills, spills, and the frenzied lunatic narratives that such writings provide.
Nothing (for me) can ever replace a physical book. But now, with the state of the art in e-ink readers, I can indulge in the best of both worlds - on the one hand spilling my coke in undulterated laughter, and on the other hand cogitating upon the vicissitudes of life!
Don