Evernote should enable its users to create documents that have semantic structure, with h1, h2, and so on. The web now has HTML5 and semantic markup. Right now, Evernote formatting is like using a typewriter, and that is ridiculous.
Allowing users to semantically structure their documents would make it possible to use that structure to improve search in the future. Image being able to search for "green" only in H1 in your notes. Image being able to search for "banana" only within a bulleted list. THAT would be a powerful app. Right now, you just have to trawl through everything.
And Markup support would be a great way to make this easier, because the way Evernote formats text is like the middle school cafeteria food - you can't tell what it is until you eat it. In other words, you cannot explicitly control the markup after pasting something in. Instead you have to waste time and energy poking and changing things manually.
I want to be able to make notes that are structured as outlines, and making it look like an outline is not the point. It needs to be structured.
Also consider Accessibility. Screen reader users cannot scan an Evernote note sent to them to find the information they need. Evernote is not Accessible to the disabled. A screen reader user would have to listen to the entire note, from start to finish, instead of skipping H1's, then H2's, to find what she is looking for.
Semantic markup makes for better search, better accessibility, and easier initial capture of information because you can organize your thoughts as an outline without having to mess with font size, bold, etc, like using a typewriter in the 1980's.
If Evernote improves formatting of text with a semantic structure, Evernote will be so much more appealing.
I have been using Evernote for over 10 years, and I have way too much information in it to easily quit, but in spite of that I am searching for migration options. Evernote streamlined earlier this year, and I hope this is the next improvement for the platform.
The future of the web is semantic content, and Evernote should not leave its users behind.