Android Espresso: Book / talk / workshop / video

I have been using Espresso for more than a year now, and I love it. I am considering writing a book / recording a video class / giving talks & workshops on the topic, but it is a substantial amount of work so I want to gauge interest before I start.

Please see the outline here:

There are 3 sections:
1) Book
2) Talk / Workshop
3) Video

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