I don't even know, but some sort of thing to be sure.
That facebook thing doesn't surprise me at all, that shows pretty internet loved. I've never seen it so I couldn't tell you why. Sure is colorful though.
the parts of the episodes where they sing and stuff is usually a lot more girly than the rest of the show, or at least after the first three episodes. If you plan to check it out make sure to watch episode 4 first, or at least don't judge it by the first two or three episodes.
I'm also pretty surprised how much it's grown over the past few months. I mentioned to some of my friends that I was enjoying the show, and right now they've seen more episodes than I have (one is a guy and one is a girl). It seems like most people like it because of the characters and how they each have a personality that really stands out, and the animation is top notch (youtube quality doesn't do it any justice). The humor is also pretty good, and it seems they manage to sneak in at least one joke per episode that only the more mature demographic would get.
it's pretty much just american anime. Not sure if I should say that or not since I know anime is a pretty big turn off for you, but I doubt you would really watch it anyway.
If nothing else, I can appreciate the animation, just from the gifs I've seen floating around and that clip I can tell it's really well done. But yeah, I don't really know if I'll ever actually check it out, due to laziness if nothing else.
I've pretty much stuck to Adventure Time for my cartoon fix recently.