While you're correct, I think the commenting and voting tendencies of the overall site population tend to drown them out. Intelligent discussions on Reddit seem to have a higher chance of being derailed by e.g. people posting 4chan cliches for cheap laughs.
Of course, he's flattering us, and he got voted way up...
I still think this site has more signal-to-noise than any other social news site except Metafilter, which is a good sign. I can still look at the top stories each day and find perhaps 20-25 that're worth at least a look, and 10 or so that generate discussions that I'm interested in participating in.
Metafilter has a $5 upfront signup fee and diligent moderators. I'm convinced that's ultimately the best way to keep out most trolling and other assorted malarkey.
Hey, I read both (though I get annoyed by the redundancy sometimes--I'm considering writing a Greasemonkey script to display:none all visited link items.)
