I just noticed a side-ribbon flyout of YouTube that, when the logo is clicked, expands to ask "What would you like to play?" I don't recall adding any extension to Google+ or Chrome that would add this. What is it for? Can it be removed?
This is Google shipping Google in your Google.
Similar to the Facebook inspired Ticker meme
Or as Google puts it,
I am afraid there is no way to prevent/remove it that I am aware of, I will look out for extensions in the meantime.