DRM is a big problem for Ebooks -- and Tablet PCs. I don't read very much except for newspapers and periodicals. So when I do read, it doesn't bother me to restrict my intake to out of copyright classics (Dickens is a favorite) or cutting-edge people like Lawrence Lessig and Cory Doctorow. I think there is potential in ePeriodicals since I mainly throw them away when I'm finished. I'd gladly exchange long-term access and searching for the limitations of the eBook physical format.
But for mainstream novels, the equation is different. I mainly receive them as gifts, and often regift them when done (I don't loan from my personal library -- I give -- if I really want it again I'll ask for it back or buy another on Ebay). I have books that have been sitting in my to-read pile for 10 years. EBooks without DRM give me something more -- guaranteed retention, ability to regift, ease of searching, better user experience. I'm willing to pay full price. Ebooks with DRM need to come with a substantial price break. I just can't trust that they'll be on my to-read pile 10 years from now.
I think the long-term solution will be DRM on initial release with an open version escrowed by a third party for release 12-18 months later. The open version could have advertising (especially for new books by the same author) and serialization (to "imprint" my name on the book -- much like libraries of old).
But I can't give my mother (an avid reader) a Tablet PC -- even though it would be great for her aging eyes -- until DRM is solved. She would gladly pay a fair price (remove the middlemen and paper handling costs and there is plenty of profit for authors, editors, and publishers) for easy-to-use eBooks. Note to publishers: the buyers of books are not the Kazaa type. And no DRM solution I've seen so far is going to meet her requirements for ease of use, sharing, and long-term retention. DRM publishers are marketing to me (lucky to buy two books a year, tech-savvy) instead of her (75 books a year, tech clueless).