You know you've got a Hacker News problem when...

When you see fun list posts and decide not to upvote them.

Oh wait, then Hacker news wouldn't have a problem. My bad.

You don't post that short, witty comment because you're worried it's too "Redditish" and will effect your karma.

When you see a misspelling and really want to correct it, but restrain yourself because it will sound snobby and you'll get downvoted.

(Your use of effect is off; 'to effect' means something more like 'to cause', the verb you're looking for is 'to affect', I think.)

When you say "where is the upvote button?" when you agree with a comment on another discussion site.

When you go to the movies and see a PG rating and wonder when pg went into showbiz.