Finally decided to come out of lurking mode to give my thoughts on the song:
First time through, I was mainly in "oh wow, new Dream Theater!" mode, so I can't really give my initial impression other than that. My second listen through is where the WOW began. That huge moment when the heaviness hits and the choir swells, the epic piano solo, Petrucci tearing it up, Myung quite audible in the mix, Mangini proving he deserves the job from the first tom rolls-so much goodness. I too get the sense that it's a LaBrie lyric, it just feels like something he'd write, so I imagine I'm way off because I suck at predicting things like that.
An interesting thing I've noticed: when people compare it to earlier Dream Theater, you get a bit of a variance of opinon in which era it actually sounds like. To me, it felt a bit like I&W meeting Awake, others say SFAM or FII, others yet say 6DOIT. Which suggests to me that it sounds like, well, Dream Theater. It doesn't sound like Dream Theater sounding like Metallica or Muse or what have you-it sounds like Dream Theater. That gives me a lot of hope for the CD's musical direction. I've loved Dream Theater since the first time I heard "Pull Me Under" way back when, but I have to admit that SC and BCSL took a bit of effort for me to get into. If the rest of the CD matches this, then I suspect I won't have to put in as much effort.