Caillou/YMMV

Broken Base: Two clear camps exist for this: One camp finds Caillou's gentleness charming; the other finds Caillou wimpy and irritating.
Family-Unfriendly Aesop: Parents frequently bash the show for teaching that whining to get your way is good.
- Which led to the writers changing his behavior in later episodes, only to upset certain viewers who actually enjoy the whining because of nostalgia.
Germans Love David Hasselhoff: For reasons unknown, Caillou is extremely popular in Turkey. Yumurcak TV, the Turkish children's TV channel that carries the show, airs a one-hour two-episode back-to-back slot at 7:00 AM and ~~two~~ three additional half-hour slots through the day, seven days a week. And to hit the message home, Caillou toys are abundant in Turkey.
Memetic Mutation: Yeah, there are Caillou YouTube Poops out there. Many of which are ones of Caillou's tantrum from the circus episode.
Periphery Demographic: Mostly parents who monitor their children's TV viewing. But others came naturally.
The Problem with Licensed Games: The iPhone apps. The audiobook app pretty much ripped the audio from the TV series and shoehorn it into some mediocrely animated storybook, while the new edutainment app is cited to be repetitive and limited in interaction.