After being a premium and business user for more than 10 years and 3 years respectively, I just created a forum account to vote up markdown language support in Evernote. It's quite a natural extension to the product and I think Evernote should implement it as a priority. It's existing editor is probably the weakest part of it's offering IMHO. In any event when Evernote first created it's edit functionality, Markdown was just a pup. By all means keep the buttons and do it as a single panel -- perhaps with a switch view implemented by a button. It is clear that we don't want to alienate those who do not use/understand markdown. My suggestion is that the native storage of notes is Markdown under the hood. It would remove the need for 'simply format' and other issues with its internal representations that manifest from time to time.