In addition to the developing world, page weight is a big concern for those of us with limited data plans. When a single log post weighs in at 2-3 MB (which is common), the day's allotment of a 200MB/mo plan disappears really fast. I often end up only reading the HN comments while on the bus since I don't want to play Russian roulette with the article size.

(of course, this is unrelated to YouTube, but to the general sentiment of the article)