I wrote a small greasemonkey script for blacklisting, it definitely helps keep the site useful for me.
http://userscripts.org/scripts/show/55745
I also second the suspicions about whitelisting being a desirable thing.
Though an interesting people list might be good - comments by people on the list are highlighted so you can spot them easier, this way you can choose the people whos comments you like to be highlighted. Coupled with a blacklist to hid (or make less obvious) the comments by people who you decide generally don't post interesting or useful comments could make dealing with large numbers of comments much much easier.
Thoughts?
That seems like a good idea.
There's a "Hacker Friends" chrome extension that does exactly this.
https://chrome.google.com/extensions/detail/mkdhfabjcebcgnpg...
This would still serve as a filter, but this wouldn't result in some kind of whitelist where you effectively only really notice the people you know you're going to agree with anyway. Whitelists encourage groupthink, and incorrectly penalize low-karma users. (Nobody is going to friend users who only occasionally comment even though the quality of their comments is really high.)
I prefer any solution that filters out the noise over any solution that gives emphasis to the opinions of popular users with high karma.