I was really waiting on this app as well. I tried out Write and I love it. It has some awesome features and works great. It doesn't have great folder organization but I upload my notes to evernote so it doesn't really matter. It has a really nice bookmark feature that allows you to mark spots in a notebook and then see them all at once on a single page. It's not as polished as penultimate but it's pretty good. Until evernote allows writing inside of evernote this will be my note taking app.
I was just looking through the play store and saw an app called Write. Only played with it for a few minutes but it looked pretty good. Not as many features as SNote (for those with a samsung note device) and it's not as nice as penultimate from what I remember when I used it back on iOS. It does have a decent set of features for a free app though. Lack in notebook organization but paired with evernote and that problem is resolved. It has some promise at least until penultimate makes it to Android.