The kids love it and I do too. One of the things that I do like about it is something really simple that looks a lot of fun. It also allows for students to create something that can go online without readily identifying them. But there is also the flexibility of the avatars to present the ideas of the students. One of the activities that I have asked the kids to do is to create a voki that talks about their passion. An activity that they already regularly do in class but here is a more powerful and exciting way to present it to others in their class and their parents.
Here's an example created by Maddy...

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