At the French Perl Workshop (and probably elsewhere before), Matt Trout talked about why and how some ideas could succeed and most other fail. An interesting talk. The last part was a rant against the numerous modules on the CPAN to parse command-line options. His proposal was to do the same thing to command-line programs (CLI) than PSGI did to web applications: formulate a generic specification, that developers can use to build applications and not depend on a specific implementation.