For example, I can post a comment decrying Blub with a snide remark (e.g., "You wrote a 1,000 line Blub program? Was it 500 getters and 500 setters?" in a thread discussing software projects) that is both information free and mean (perhaps Blub wasn't the author's preferred choice, but chosen for him or required in order to build an application for the iBlubber). People on this site generally dislike Blub, so the comment will get upvotes without adding any value to the discussion (an example of adding value would be saying you were able to do this in 100 lines of Flub using its cool new hygienic macros with a link to a paper on hygienic macros in Flub).
That's not to say all comment score data should be gone. Comment scores can still be kept and comments could be displayed on stories in the other in which they're displayed now (a mix of comment score and how recently it was posted). Generally, what I've found is that comments showing up _first_ tend to be of higher quality i.e., overall algorithm works more often than not.
[NB: I work at LinkedIn and we do this for connection counts-- we want users to network with each other, but we don't want to make it a "who has the most connections" game, that's why when you have over 500 connections (which is perfectly legitimate and allowed), only "500+" is displayed as the count on your profile]