Okay, I've only gone through the first two levels on the easiest setting but I can already say this:
PRODUCTION VALUES! Wow!
This is, IMHO, the best looking game on the Wii to date! Seeing the levels both before and after the disaster, seeing crowds of people, and absolutely the BEST voice acting and facial animation I've seen in any game for the Wii to date.. this game blows me away! You know how you have to do levels in Fable II where you "bond" with the other characters through their "cleaver" dialog.. well it actually WORKS here. I can't get over what a great job they've done creating characters, building a story and drawing you in. I would have thought that in an on-rails shooter I'd miss the exploration and discovery of Dead Space on the HD consoles, but they give you a few sections where you can look around a little bit.. and there's a LOT of boxes and items to get.
Just as with Dead Space on the HD consoles I'm having ammo problems. I need to work on using the right tool for the right job.. being forced to take out that last wave of necros with just the rivet gun is kind of painful. There's some strategy here, some exploration and a whole lot of personality.
What strikes me most is how different in tone the game is to the first one. You're not the only person left alive, you're part of a whole world that's falling apart around you. There are all these other people surrounding you, and they feel like real poeple, not like automatons spouting pre-recorded dialog.
You fence-sitters out there - GO GET THIS GAME! If you don't pony up for something spectacular like this then you don't deserve third party support!