This is my favorite song in the Billy Joel Piano Challenge pack.
First of all, be warned, it lives up to the name of the pack. It's very challenging. Even harder than Paradise by the Dashboard Light, I'd say.
Like Meatloaf's classic rock opus, this song also contains many movements, which all sound and play quite differently from each other.
This song makes use of several techniques, including scales, arpeggios, and a metric ton of chords and chord types which it likes to throw at you pretty rapidly.
This being mostly a ballad, the piano is second only to the vocals and pretty much carries the whole song. It's played in a somewhat improvised manner, so even sections that repeat contain variations which keep it interesting.
The only problem I have is that the solos are way harder than the rest of the song, which is already pretty hard. But they're short, and if you can play the rest of the song okay you can probably pass it.
If you're a skilled player, and are getting tired of simple, repetitive, or otherwise boring keys parts lately, then this is exactly what you've been waiting for.