Yes, it is nice to have a introduction clip for a longer videos, but I feel it is sometimes not needed for shorter videos.
Plus, it gets kind of repetitive if you are watching multiple videos by the same author, and have to watch the same old title sequence and ending for every video.
Honestly, I'd be like just get to the point already.. it is bad enough that some videos have forced advertising before you even get to watch the video.. and then to have to sit through an introduction? Please. Leave the intro in the description of the video were in belongs.