You can't thumb up on Youtube without a Google Account (which is not exactly the same as a Google+ account).
And, I already get the +1s (or thumbs up, or whatever it's called) of the people I follow on Youtube, in my Youtube stream. And I do like things there. On the other hand, sharing ? I'd think twice before doing it.
And, I already get the +1s (or thumbs up, or whatever it's called) of the people I follow on Youtube, in my Youtube stream. And I do like things there. On the other hand, sharing ? I'd think twice before doing it.