You don’t want anyone to know what videos you are uploading, watching, liking, commenting on or any of your activity from YouTube to show on your Google+ page or stream.
The good news is, there is an update concerning that, YouTube will no longer automatically post your activity (uploads, liked videos and so on) on twitter and Google+,
In an email sent “After January 31st, the ability to automatically post YouTube activity (uploads, liked videos, etc.) on Twitter and Google+ will no longer be available. We’ve found that sharing these actions with a custom message (instead of through automatically generated posts) provides a better experience for the sharer and their followers on other social networks.”
The email went ahead to say that “You can continue to easily share videos to your social network” by using the Share button on a video’s watch page.”