The iPad is being marketed with e-reading being one of its main features.
So I see no issues with discussing how well it does at that task. Most everyone I know that has or is interested in an iPad is interested in the e-book function. Maybe not as their main reason--as like me none of them are bookworms--but people are aware of the function. They show the iBook app a few times in the TV commercial etc.
So I see no problems about articles discussing that feature and how it compares to the other options for reading e-books. I do think such articles should be fair and point out the advantages the device has in terms of all the other functions it can do.
Because let's face it, the vast majority of people don't read enough to have much interest in shelling out $200+ for a dedicated e-reader--so for the mainstream being multifunction is a big selling point.
I want a tablet, and I will read on it. But I'll no doubt spend more time surfing the net, watching videos, playing games etc. based on my experience messing around with my girlfriend's ipad.
In a same token, there's no need to be so harsh on eyestrain etc. as the average joe isn't reading for hours a day like the people on this site. I seldom read more than an hour or so in a give stretch so I can read on pretty much anything. Articles should mention that eyestrain is really only a concern for most if they're doing long term reading etc.
But that's just a problem with any reviews/articles etc. as they're all just one person's biased personal opinion, so people shouldn't make to much of them nor waste time arguing over them. In the end of the day the only thing that matters on gadgets is your opinion on them and whether they fit your needs or not.