I actually found the comparison chart fairly useful when I made my jetBook purchase. But as with anything, you have to take it with a grain of salt. Anyone see Microsoft's Internet Explorer vs. Firefox vs. Chrome comparison chart?

All the tech people I know admit that it is a pile of *ahem* garbage. So I don't take marketing too seriously.
For me it came down to the price. At the time, the cheapest I could get a new Sony PRS-505 was $260 (now on sale at Costco for $199?!). For almost $100 less, the jetBook was a no-brainer. And of course I had fun dying it. On the other hand, I don't think the jetBook will be competitive at the $299 price range now that we have a bunch of nice 5-inchers coming out. If the Astak reviews are favorable, I might switch devices.
As for the screen -- some people think it's great, others not so much. It IS comparable in a certain sense to e-ink and is NOT like the LCD display on your laptop with the backlight and glare. If you want to see "yesterday's" LCD technology, take a look at the EB-1150. It's come a loooong way. I'm looking forward to the upcoming promises of laptops that will be able to switch between the standard LCD and the reflective type that the jetBook has. Now that would be nifty.