I think (I'm only guessing) he means this "[L]et's face it, there are a lot of people who don't even own computers now because their iPhone and/or iPad suffices."

To the best of my knowledge you need a computer with iTunes installed to start an iPad at all. A home without any other computer means that your iPad is a flashy paperweight. Also, it's really far too early to tell if the iPad (which is being sold in huge numbers) will replace other things or (as I think Apple hopes) supplement other devices.

Edit: Please notice I say "iPad" above. You respond by talking about the iPhone. They're not the same in this regard, I think. The iPad requires a computer with iTunes to start it initially.

All of that said, I agree that their current model really should change. (Also, the pop-up message in the blog is stunningly obnoxious in wording. It's approaching the "bomb + ok" level of bad.)

That was exactly what I was getting at. It's also not a matter of "is it technically possible" but (s)he claims that it's a popular choice. I don't buy it, but would love to be proven wrong.

I thought you could activate an iPad with a 3G plan at an Apple store, and then you wouldn't need a computer from there on out? Or am I wrong here?

You may be right. I haven't heard that the 3G model was different, but I can't say for sure that it isn't.

The absurd claim about the "iPad only home", given that the iPad requires a computer to activate and manage.

Apple has gone out of its way to make sure the iPad is treated as an additional device, not a sole device for a user. This is important because it allows (or at least helps to allow) the iPad to be judged on its own merit for its own uses, not as if it were the general-purpose computer that some (critically: not Apple) like to claim that it is, much to the iPad's detriment.