Color and Motion. And DVD SP.
We use them all. Color as our main, dedicated grading package, often used by a colourist who spends half her life in Pablo and grew up on various DaVinci and Pogle systems, who rather likes it. Motion, which is much ignored by the AE set, still has a very tasty motion tracker. Both have been primary tools on million-dollar-plus projects for us. DVD SP is just the simplest way to do complicated screeners, and quite OK for release projects. Blu-ray would be nice, but I guess it's too late for that.
We use FCP because of Color (and Final Touch before it), not the other way around. Yes, we'll always have a copy of FCP kicking around, like we have Premiere Pro, as a workflow tool to get us into the places we need a project to be for a grade. But if Color's dead or deprecated, then we'll be going elsewhere, and that could be Avid (where most of our cuts originate), or it could be Resolve, or Baselight (please, not the plug-in), and whatever apps best feed it.
If, on the other hand, Color and Motion have vanished in anticipation of the much-rumoured Phenomenon (working title) then I hope it's good, I hope the workflow actually works, and I hope it costs a great deal more than $299. Like $2999, and very hard to crack. Then we'll once again have something that not all our clients have on their MacBook Pros, and a suite, with all its expensive peripherals, that can again be sold for money.
Avid has long understood that free/cheap apps don't help professionals earn a crust. I hope Apple isn't vacating that space in favour of the weekend enthusiasts wanting a fruitier version of Final Cut Express. We'll love it, but we won't stay.