Yup, and here are some suggestions: (sigh, maybe I'll see if I can get this through their suggested email support as well... will that actually help? Editors: what say you? Does this stuff speak more loudly to the higher-ups if it comes through certain channels?)
Keep some space for ads if you want; I don't give a shit and I realize you've got bills to pay. I have the option of turning them off, but I don't because I like the site.
That said, information density is important. If you bump the font size and line spacing or significantly drop the comments column width, we can't read the comments or their surrounding comments' context. There'd better be a lot of lines before I have to "click for more", and I never want to have to "click for more" on the front page. This might mean reducing the size of those terrible banner images.
We need to be able to easily see the information on posts and navigate the discussion. Links to parent posts are absolutely necessary, current score, subject, and at least a preview of the post content if it's collapsed. Other useful information provided that I'd like to see stay prominent includes the username and UID number of poster. It was tough for me to get used to the collapsed/non-collapsed system with the last redesign, but it actually ended up giving a lot of information in a tight space and generally reserved more for better comments.
As it currently stands, the two problems cited above alone will kill the discussion oriented nature of Slashdot, users will desert, and revenue will tank.