Hi Damian,
It's true that Spring Roo is exclusively for developing Spring-based applications. I don't see a reason why someone would like to use anything except Spring for developing enterprise
Java applications
Yes, Spring Roo can be used for creating Spring Web Flow projects. But, the current support for creating Spring Web Flow projects is limited. Currently, Spring Roo only generates a sample flow to help you quickly get started with Spring Web Flow projects.
The JSF add-on is currently in development and I think it'll be available in Spring Roo 1.2. Please refer to this JIRA issue for more information:
https://jira.springsource.org/browse/ROO-516
regards
ashish