Digital Rebellion has an excellent article on 18 features that Premiere Pro must lift from Final Cut Pro, some of which I have covered extensively (like showing clip duplication in the timeline) and others I had not even realized, but all I agree with are necessary for Premiere Pro to really replace Final Cut Pro.
Though I doubt you will ever be able to open multiple projects as you can’t in After Effects either (only import projects into each other). Still it would be nice!