From the Simplenote blog:
Finally, we’re going to loop back on some of the most popular user requests, including an Android app, Mac app, and native support for Markdown while of course preserving the simplicity you’ve come to expect.
Simplenote (and NValt for that matter) is the app which brought plain text note-taking and ultimately Markdown to me. And it was the first app that I have used religiously both on iOS and the Mac (NV and NValt). It’s great to see that it is still being developed.
Looking forward to see the app being released since I never really found a decent replacement for it.