I hope that Evernote does the right thing... I had the same discussion with other companies, where I decided to immediately cancel my subscription and delete all data. I wouldn't hesitate a second to do this with Evernote once the start "reading" my data regardless if it's machine learning or human curiosity.
I belive not every company has to make money out of big data.... and that^s obviously the goal (opposed to make it better for customers).
My five cents