My daughters have just discovered Shopkins....with gusto!
I find some of the paint jobs to be sloppily done, and some of them are especially small, but the kids love them. My two-year-old only ever has one at a time, and she is constantly losing it. My five-year-old has a small collection of about 25 or so and knows all of their names.
The two of them happily play together with them for hours at a time, acting out all kinds of scenarios. They seem to be a hit.
When they got Christmas money, they both wanted to go out and get all things Shopkins.

These toys made in big with seasons 1 & 2.. Now season 3 is making it BIG! My daughter is super excited to add these to her collection! They come in a small shopping basket ( which is now re-stackable) with two blind bags & that's the whole surprise, kids don't know what their going to get until they open the bags. They've added new categories & playsets. Very cute!