We use both YouTube and Vimeo here at Anticipate Media. But Vimeo in particular are our friends, and they offer robust privacy options that really help share and deliver content to our clients.
I was not surprised that Vimeo has announced a new copyright protection system. It's a necessary thing, really. I was however surprised that it will flag even private videos. These videos often contain temp music that will never be made public until purchased.
Theres a human review process for this. However this could take time.