All you viral marketers should be studying this event carefully. Something definitely was done right in promoting this.
What if this was for a product you wanted advertised and not Justin Bieber? Imagine the publicity you would see.
The key here is it was not in your face. It was subtle. It was something that people wanted to know more about.
Can your marketing team reproduce this for you? Yes "It can do that" you just have to do the research.