To briefly mention the subject of the thread
Had my first chance to get my hands on an iPad this evening.
I emailed myself some pdfs of small extracts from a couple of magazines and a couple of comics to try out on the screen.
Really was better than could have expected, the comics were perfectly readable (as single pages, not double spread), and really looked good. This could be for comics what my eBook reader is for normal books for me.
For eBooks, I was slightly disappointed. I like reading with small fonts, and I did find that the reduced DPI vs my PRS-505 showed, the smallest font sizes (in iBooks) did become a bit blocky. Setting both to an equivalent small sized font, I think the PRS-505 would look better, however, I think that scaling the fonts to give the same text shown across the width of the screen in both, the iPad would look better.