CPUs are magnitudes faster today than they were 10 years ago. Why is it that pages still take seconds to load? Go back 10 years and they still took the same amount of time. Why?
The two major updates so far this week: Google Chrome, which now renders faster, and flickr, which has significantly more complex and larger graphics. As things get able to and display process more, more is asked of them. We aren't targeting 580px wide simple HTML, no CSS and 15 color gifs. Nor are we targeting a single platform and the simple display of information. Even if you're just displaying stuff, if you're doing it right, you're divorcing content from presentation and sending a handful of files for each page: each a solution to a problem that was at one time annoying. Or "solved" poorly with the likes of early Frontpage or Dreamweaver.