I just figure that no matter what future devices appear, it's pretty certain that formats like plain text, HTML, RTF, etc, will either be natively displayable or, at least, convertable to it. That's all that concerns me personally. Just like with music players, they may support their own native DRM formats, but I can be pretty certain that I'll still be able to play my collection of MP3 files on them.
I sincerely hope that Reader is
completely obsolete in 10 years. Heck - I hope there's something a lot better around next year. I'll be mightily disappointed if there isn't