I agree... :) it would be nice for all of us to be able to "publish" ourselves... but for the most part, even if we did have better low-power home servers and enough bandwidth to serve the content, most people won't be able / willing to set it up. So, I think in general, the mass-public will be stuck with the Bloggers and YouTubes of the world.
When you buy hosting online, you buy more than space on a hard disk.
I don't think most people really need high availability, so UPS and redundant connections sound like overkill. For fail-safe hardware, we just need something "unplug proof". A Beagle Board (with a few GB of Flash and a small battery) is more than enough.
I am aware that such a solution will be a little less convenient than storing everything "in the cloud", no matter how easy it can be. But the cloud has its downsides as well: you hardly have any privacy in the cloud, and they can shut everyone down, for any reason.
About aggregation sites like Hacker News, you do have a strong point, though.
[1] I mean as easy as Facebook, Blogger, YouTube, Twitter… Any harder and it won't work.