I haven't owned a DR1000 (yet) but have had an iLiad. I think, for comic books and such, you should go with the larger screen. The iLiad is nice, but not quite large enough for that (at least not in my point of view).
I have also recently looked into the DR1000 and from what I can read in the posts in the dr1000 forum, it sounds like the software has now matured enough, and enough bugs have been fixed to make it a good buy. Also, some of the owners of DR1000 have had iLiad's and i got the impression that the DR1000 is a good deal better. It might have its quirks, but in my experience all ebook readers have that at the moment - I htink we are still a few years away from hardware and software that is that good (it's like computers were 15 years ago)
As for the release dates; the DR1000 was released Oct. 2008 and the 2nd ed. iLiad a year earlier. The 'Book' edition referred to in the matrix is the 2nd ed. without wi-fi and silver instead of black (says so just below the dates in the matrix
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