If this article at MacRumors is to be believed what became iMovie 08 and later FCP X was supposed to be an app to quickly make rough cuts that would export to finishing in FCP. I wish that was all it was!
From that experience, First Cut was born which would let you import your raw footage and quickly skip through, organizing and building a rough edit. The intention originally was to then export to Final Cut Pro. At some point, Apple officially latched onto the project and turned it into the new iMovie ’08.
I just wish it had stayed that way!