I have never thought about You Tube as a massive website where communities are created. By watching these videos, it made me think that this medium is based on the same principle as a blogging; sharing a video record is the same as sharing a written text.
People who post videos create artistic pieces that represent their own or new identities. Technology enables people to hide behind it. As mentioned in video, it creates a shield that may cover the truth, the authenticity of author.
In what way does technology influence our language? The answer to this question is speculative. I think it opens new vista for language. It adds new words in our dictionaries and language become more interesting. On the other hand, an impact of new technologies on language has a weak point. By using technologies people become lazy to handwrite which decrease their ability to know the exact proper language.
A language used in these videos is very informal. I assume that a choice of language in videos or other blogs depends on what message/art the author want to send to the world. It depends on type of genre.