Absolutely fantastic, from start to finish. The visuals and atmosphere breathtaking, I found myself just standing around at the beginning listening to Will The Circle Be Unbroken for a while before moving on.
I have to say though, aside from being massive racists (not entirely unexpected in 1912) I found the people of Columbia fairly likable, and felt pretty bad about how probably most all of them had their lives ruined at some point in this game.*
Elizabeth not being a massive liability was a nice change from other games that pair you with an AI companion that you are ostensibly protecting. If anything having her around makes things substantially easier, what with all the ammo, health, and salts she keeps finding.
My only complaint is the same tried and true complaint for any excellent game. I just wish there was more.
*Spoiler-ish: Though given how the game ended, I suppose the argument could be made that none of them were ever there in the first place.