As an Apple Certified Trainer for Color, and the other FCS2 apps, I can tell you it's about the EASIEST to learn. It just looks weird when you first open it up. But then, so did FCP to most folks the first time they saw it.
Super simple to use, but there are tools and commands that aren't really obvious. You really do need a three button mouse w/scroll wheel (the third button being the scroll wheel), or you'll have a tough time working it.
The Peachpit Press book Apple Pro Training Series: Color, is about the best training around. Comes with a DVD full of lessons and media, so as you go through the book, you are actually doing the work. I could rant on about how your brain learns, but that degree in Ed. Psych gets me in trouble a lot.
Don't be intimidated, it's an awesome app, easy to learn. The hard part is learning to see color, contrast, and composition. Things a book can't teach you. The physical tools are SUPER easy to learn.
Remember the very first time you looked at an NLE?
As for the interface, it's like that for a very, very, very good reason. All Apple will do is improve the text quality. But the gray and layout are purposeful, which the book will explain.