On the Windows Live Team Blog, Cheryl White (a Program Manager for Windows Live Movie Maker), has detailed some of the new features in WLMM along with the rationale for changing the way things are done compared to Windows Movie Maker.
Take a look at Windows Live Movie Maker – What changed in the new version, and why. For the time being the post is open for your feedback. Should it later be closed to commenting, feel free to post your constructive thoughts here.