I've never cared about minor spoilers, so I'm a bit loose-lipped...for example, if someone in the comment section were to say "that character's so annoying; god i hate them" I might say "They won't act that way forever ;] ".
I can see someone who hates spoilers getting annoyed with me for saying even that much, but in my book that's just an appetizer. Gives you something to speculate about for the future~
Outside of formal comic spaces, however, (i.e. my DeviantArt acct) I'm even more loose-lipped. There are spoilers everywhere; if I think a comic is a long way off (and to be honest, most of them are) I'll say pretty much anything about it.
It's hard to feel motivated to keep secrets when it seems that no one cares, after all...in all my 5-6 years on the site I've only gotten one "wait, isn't that a spoiler" comment...and that wasn't even really a spoiler. =/