Is Pipelines architecture cost effective to adapt, compared to existing frameworks and architectures?
Its very cost-effective, because it takes maximum advantage of the hardware and applications you already have in place. In fact some of the examples in the book use Spring and pipelines together, to show how this can be done. Support for commodity multi-core hardware is a key intent of pipelines, with that you can scale to very large volumes far less expensively than traditional SMP or mainframe architectures.
Also, is there any new roles will be introduced when adapting this new concept?
The book discusses the roles required, and we did introduce the idea of a "pipelines architect", but of course this is just a new set of skills for existing architects.