Recently purchased and still exclusively use an Archos 80 G9 for my ebook / digital comic reading. I used an iPad but it seemed a little too unwieldy for comfortable reading. I also tried the nook Color, but found the 7" "widescreen" format a little too cramped for digital comics and heavily imaged books (had to constantly zoom in and out).
The 8" Archos screen at a 4:3 ratio and 1024x768 resolution is the best compromise for me all around. It's no too heavy for long-term reading, the screen is very nice for comics and so far I have gotten very good battery life (7.5 hours minimum up to 13 maximum between charges depending on the usage from movie viewing to basic web access to reading).
Oh, and they are constantly on/off sale at your local Staples for $199.