"Your eyes aren’t cut out for staring into a light."--what nonsense. What else are your eyes seeing, if not light? Whether it's emitted light, reflected light, transmitted light, refracted light, light vinaigrettes with light Benedict with a helping of light Julienne on the side makes no difference. As far as your eyes are concerned, light is light.

As Doctorow teaches, the only thing that matters in a case like this, does it scale vastly better than the old medium? I do not have the definite answer... it's surely not as big change as the printing press was over manual written codexes. However the traveling crowd may love it and that's not so small crowd.

Sony's got a new version of their reader out, its priced at $300. That buys a lot of paperback books (which is what one large publisher announced recently is all they're going to make in the future).

All this technology is usable but unfortunately its just not cost effective yet. The reader has to be priced at a point where it can be lost before this technology will be usable to the masses. (It could also do with some extras like audio/video......)

It seems the writer doesn't really see the full potential of e-paper. It could be that 399$ is too expensive (it is) but prices will go down and you will be able to buy a sub 200$ device by the end of 2008 if not before that.

It also seems that the writer knows very little on e-paper in general - Like the fact that they do not emit any light (unlike LCD for example) - see here for more:
http://www.tfot.info/articles/1000/the-future-of-electronic-paper.html

People have mobile phones. Same principle on that, so sorry I don't agree with the first reasoning. Also, paper is heavy, especially on longer trips or when you need reference manuals.

As for the second, quite, this is why any truly serious e-reader these days will be e-ink.

I have the original Sony Reader which I bought before a trip that involved a big amount of hours in planes, trains and lines, and despite it's flaws I am very happy with it. Even after the trip I've been using it with no problems. Now, it doesn't replace the feeling of pages in your hand but, does it really matter? For some it does but for me it's a matter of getting use to it. 

Now, the pictures from the Amazon device make it look seriously clunky. Do you really want to browse on ePaper?

According to the engadget writeups, Kindle is an epaper reader, which is why it costs $400. In other words, no staring into a light with this.