Bit later than I had intended, but here's some initial thoughts on the characters, based on only a tiny percent of the book. Also see the typos thread for the source of some clarifications I discuss here.
The "production description" bit on the Amazon page on the book suggests the main characters are: Dalinar Kholin (who we see "slumped drunken at a small table" in the prologue), Kaladin and Shallan. Doesn't seem like we'll be seeing too much of Szeth in this book - quite interesting how he's so powerful yet so constrained at the same time and clearly has a rather different culture.
Not much to say about Dalinar yet. Is he on the Shattered Plains, with the Alethi king? (Or at least, where the king was in chapter 1). Who's the Shardbearer at the end of chapter 1 - anyone we know? Meanwhile, his niece Jasnah is off on some major journey and is considered to be both brilliant and a heretic. Jasnah seems like someone to cause big upsets and it seems quite likely she could drag Shallan into something much bigger, whether by accident or deliberately.
Kaladin's situation is certainly easy to grasp quickly. A branded slave waiting to be sold. Just about hit rock bottom mentally, physically and socially. But he also has significant experience as a soldier and has some kind of training in medicine. I wonder how he will connect up with the other characters - not sure where he is located in relation to the others, but I can imagine Shallan finding his experience and knowledge interesting, for example. Normally when you start with a major character starting from the "bottom" you rather expect them to rise up to great heights. If this is going to happen with Kaladin, it looks like he's going to be carrying a lot of baggage for some time - his last attempt to make a difference didn't end well.
I find Shallan's situation pretty interesting - she has a certain amount of freedom, certainly more than the other characters we've been introduced to so far. Normally in fiction, you'd expect to see her situation from the "start" (ie her father dying) and then her setting out, but given that it's taken 6 months for her little quest to get anywhere worth mentioning, maybe such an introduction would come across well. It also gives me the feeling she won't be returning any time soon because we're not presented with an in-depth introduction to her family and manor. I suspect she will be lucky to be returning home by the end of the book.
That Amazon page says "Though she genuinely loves learning, Shallan’s motives are less than pure. As she plans a daring theft, her research for Jasnah hints at secrets of the Knights Radiant and the true cause of the war." I would guess that this theft is from Jasnah - a heretic princess from a different country, and outside both their own countries, could make a decent target. I wonder about a couple of things - could survive her family's predicament simply by sticking with Jasnah? (ie don't take any risks and simply give up on her family) If so, then maybe Shallan could find her bridges burnt for her - that bad news about her family could catch up with her. After all, it's been 6 months - a lot could have gone wrong in that time.
The cultural situation women are in, at least with Shallan and others (related to the Vorin faith?) is rather interesting. I can't think of any historical equivalent to this freehand / safehand cultural thing for a start. Pretty rare to have such blatant asymmetry as well in everyday dress, as far as I'm aware. I wonder what kind of historical events led to this. I also wonder how carefully covering / protecting your "safehand" is "modest"? What kind of immodest things are possible without it being protected...? Also, is it always your left hand that's your "safehand" - in which case, left-handed women might be forced to become right handed. It looks like in the Vorin culture, with the exception of "ardents", only women study reading and writing apart from glyphs. Looks like a lot of clerical type work is women only - notice the "women in red coats tracking cargos on ledgers" bit. Looks like research and the like is considered a profession for women only - I wonder if this is global, mostly global, or specific to the Vorin faith. I wonder how educated noble males are in this world, and how common highly educated males are - Kaladin and his father have some medical knowledge and they're Alethi. Is this an exception for doctors (no women on/near the battlefield). What about the opposite - have there ever been women Shardbearers?
Shallan herself seems quite interesting - lots of scope for development. There seems to be a "real" Shallan in there somewhere, ready to throw off the constraints of "proper" behaviour. Considering how unfamiliar this all is for her she seems to be handling things quite well. Will be interesting to see how Shallan's tongue fares against a noblewoman