Remember the kinder, gentler YouTube comments powered by Google+? Well, they're finally rolling out across the internet, and the Android app is no exception. Like it or not, Google+ is all up in your YouTube.
If you go to make a comment on a video, you'll now see your Google+ avatar next to the field. The default setting is also to share to Google+, but you can uncheck that box. This is actually a neat way to do things – it works the same as if you had shared the video with a comment directly to Google+.
This is all happening in the YouTube app on your device right now – there isn't a new update to wait on. So go and comment, but be nice.