I really don't understand why Evernote misses this opportunity. When I do the notes, I don't really need all rich-text flexibility, i don't want to care about the style - what I really want is a way to structure my thoughts with headers, lists and tables. And it is perfectly solved with Markdown.
Btw, the markdown may be displayed with different styles, which ones even may be sold in the internal store - so it is even an opportunity to increase sales per user.
I don't want to switch to another tools, but with no markdown support I would not have a choice in recent future.