bump for this one looks really promising!!!
Still looking for this one. Thanks!
I have this. The secret kindle mega niche is summary books.
Can't share it because I'm not at my computer right now.
Piggyback Publishing Profits by Harrop and Drum is much better and has been shared here already.
I tried looking for books to summarize with Kindle Spy and KDP Rocket but so far I have not found any that would be profitable. Even the ones that look like are successful don't look like they are making much. Maybe no one is leaving reviews?
Any way, hope this helps.