actually, i would argue there kinda is. even a written page is much more prone to having shadows cast on it, and is pretty awkward to hold when the pages-read to pages-to-read ratio is wildly disproportionate. hell, even turning the damn page is much much easier on a kindle, though i would acquiesce this last point is not of much consequence, unless you're someone who reads while out of doors and don't want to take off warm winter gloves to turn the page of your book (this happens to be the case for me).
nonetheless, having something that doesn't constantly have shadow cast all over it and that feels uniform and comfortable in my hands is a huge deal. ADDITIONALLY, an e-reader makes reading internet and magazine articles about 100 times more enjoyable. long internet articles are not things i have to sit at my stupid computer leaning on my elbow for an hour to read--i shoot them to my kindle and read them while i'm sitting outside, or walking on the treadmill. i switch from novel to essay to article back to my novel, depending on my current whim, and all that stuff is always with me.
the allure is undeniable.
i still like books, but the truth is, switching to kindle increased my reading tenfold. the proof is in the pudding. it's made reading much more enjoyable for me, and everyone i've ever known who has bought one.