Oddly, I tend to get the opposite impression: If a lot of people voted a story up, yet few people felt the need to add something, complain about it, ask questions, &c., it suggests that it's something both very interesting and high quality.

Conversely, few upvotes and lots of comments seems like a warning sign about the article.

I actually disagree. A high upvote to comment ratio is usually indicative of a great link.

It's indicative of a link that answers a question, not one that asks it. So what you should weigh is controversy / (votes / comments). A high-vote, low-comment article about abortion has clearly resolved the issue; a low-vote, high-comment issue about creationism has probably just asked stupid questions in a provocative way.

It depends on timing, too - there have been several times where an interesting and fairly substantial link was posted, and discussion seemed to hold off for half and hour or so because people were actually reading it.

What about the links where the information is basically just an announcement (see the links related to Google's public DNS servers) and a ton of discussion is then generated here over 'what this means', etc?

Fair enough, I'm in the clear minority:)

I too prefer to read those articles with many comments. (I usually read comments first, and then decide based on that if I should bother reading the article). However, I do not think the ranking needs to change, the number of comments is clearly visible on the home page, it's easy to just skip those links with little or no comments.