My native language is not English and I don't understand very well a domain like youtube. For example will be ok YouFreak.com meaning you are freak? (You are tube) Or is more like YouSurfboard.com meaning Your surfboard? (Your tube) Thanks
Youtube works because YOU sounds a bit like TUBE - they rhyme.... but I think youtube made it big for other reasons, not just because of the domain name. They were among the first to allow people to stream videos online with a flash player (which most browsers already had installed at the time).
I think it matches neither one of those two examples. I think it is more like a brand name. I never thought of youtube as you + tube before... it's like two words together, like McDonald's.