Had a opportunity to talk to Matz, the creator of Ruby Programming language. Some thoughts he shared were, he understood language projects as typically a very long term ones, something like 50 years. That is, if you get involved in writing a new language, the project could keep you occupied for about 50 years. He also mentioned that writing a language is easy, the subjects are taught well and books are available, but designing a good language is a hard task.
It was very entertaining and enriching to hear these thoughts from him.