[xseven]

HN is not as mainstream as Twitter or Reddit, so I don't think we can really compare it that way

[dabockster]

I wouldn't necessarily consider Reddit mainstream either. Sure, it has a lot of users. But I don't hear people on the streets telling each other to look at their subreddits.

[gedrap]

If we can trust in Alexa, reddit is #26 globally and #9 in the US. Even with some error margin, that's damn mainstream.