According to the latest stats revealed by Google, it seems that Android Oreo is now sitting at 12.1% distribution, where 10.1% of it is for Android 8.0 Oreo while the remaining 2% is for Android 8.1 Oreo. While still somewhat low when you look at older builds of Android and when you consider iOS 11, its adoption is somewhat steady.
You might recall stats from back in April where Android Oreo was at 4.6%, so for it to go to 12.1% in about 3 months is pretty decent. As for the older versions of Android, Nougat still seems to be the highest at 30.8%, followed by Marshmallow at 23.5%. Gingerbread is still clinging on at 0.2% but we imagine that it should soon go the way of Froyo and Eclair where it should eventually drop out from the charts.
That being said, with some of the efforts Google has been leading such as with Project Treble, perhaps Android P will paint a very different picture.