I'm migrating from Microsoft OneNote to Evernote and one of my biggest gripes is that Evernote does not have pre-defined styles. In particular, heading styles (h1, h2, h3) that I can access through a keyboard shortcut.
OneNote 2010 has that feature (although I can't modify them). I would pay for a special client just to have that feature in Evernote. Sure, I can change the formatting manually, but it gets very tedious to change the font, the size and the bold for every heading I'm creating.
Another style I use all the time is for code examples. Courier, 9px, no bold. I'm sure this is not a requirement just for me.