Google might be pushing their Google +1 Button on their YouTube platform a bit too much with a new update that is being seen by some users.
The company seems to have removed the Like/Unlike buttons. And in place you have a Google Plus Like button.
Clicking on it gives the video a +1 and you get the option to share the video on your Google Plus Profile.
All is well but you no longer get the option to give the video an unlike! Here are some screenshots: