The "Cathedral and the Bazaar" was considered a ground-breaking work by the
open-source community, and by many other software engineers who have read it.
Many projects switched to the Bazaar style and found an increase in
productivity.
Still, some developers have not yet read CatB and use a mixture of Cathedral
and Bazaar elements in managing their projects. When I read CatB in 2002 I
regretted I had not fully read it earlier, as I was already full-way in
developing and maintaining a mature project.
Many software shops, who cannot afford to fully open-source their code (from
various reasons), have adopted some of the concepts put forth by CatB and also
saw a boost to their productivity.