My biggest complaint on most of those sorts of sites are:

    * Tight line spacing
    * Full window width lines
    * Small fonts
    * Sometimes, font choice

When I'm reading something lengthy on a site like those named, I'll usually set a max-width on the body, give it auto margins, and play with line-height, font-size, and usually set it to Arial. Takes me 30 seconds on pages that aren't terrible and makes it much easier to read.