The web is a low resolution, low fidelity, crappy medium....etc...you can go read the rest of the piece if you want, I replied:
A quick gut check: Would you ever hang a web design on your wall?
Couldn't disagree more. There are plenty of web designs that I would project onto my wall (or maybe display in a digital frame)--printing them would be impractical because of the low resolution you have at the center of your argument. Also, those sites I would choose to use as art would not be the content-centric ones you mention (although there are some that make the aesthetics of text true art). If all you think of when you think of the web is TechCrunch and CNN then no, certainly not. But there are some amazing artists doing work designed and delivered on the web. Similarly, there are some very famous artists who used low-fidelity technologies centrally in their art.
Your other arguments fall apart equally as fast--looking at a painting is a solitary experience abstracted from our sense of touch and smell, and yet the visual arts is one of our primary artistic forms.
Also, it's 2010! If you are bashing the web based on bandwidth and screen resolution, where were you in 2000, or 1995?