Well, tangents are good in conversations once in a while, but they really should try to make some kind of return at one point.  Posts that have absolutely nothing to do with the topic at hand, or really simple posts (saying "I agree" and not explaining why, for example) are spam.

I think the word "spam" is somewhat abused in Abandonia.  The slightest tangents from the topic at hand are classified as spam, and often anything someone says that the majority disagrees with is also considered spam.