This still makes me laugh.
Here's Kobo's newly rewritten content guidelines on prohibited content.
It's a couple of pages long, but it's very clear. I didn't c/p it because it's way too long.
Here is the equivalent of the Amazon Guideline.
BookLikes Source: http://krazykiwi.booklikes.com/post/640426/guidelines-vs-guidelines-
Which I will c/p because it says:
"Pornography: We don't accept pornography or offensive depictions of graphic sexual acts.
Offensive Content: What we deem offensive is probably about what you would expect. "
Yes, both sites disallow stolen, illegal, etc content, but this is just comparing the parts about offensive/explicit content.
The difference is striking: Kobo (now) makes it very clear what they will and won't allow, that they will use interstitials to gatekeep this content, and that going around their rules will get you in doodoo. Amazon more or less says "well you figure it out, duh".