This looks like a longer form version of Somewhere (http://somewhere.com/, posted last week here: http://www.producthunt.co/posts/636).
As I mentioned in that thread, blogging is super challenging for most people and one of the biggest friction point for people is finding a topic to write about. I like that Readwave provides focused collections and prompts to inspire writers.
Its tagline "Write your 3-minute story" made me think it was more constrained but it's actually limiting writers to 800 words which takes ~3 minutes to read but several minutes/hours to write. :)
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