I played a four-player demo at GenCon and enjoyed the experience. Even though three of us were newbies, it took about 90 minutes for a full game with the expansion. Most of the time it is just my wife and I to play. For those with experience, how does the game fare in two-player mode?

There is a bit more manipulation in the 2 player game with regards to the King's Reward and King's Envoy being used.

two players are unlikely to consume more than 30 minutes of gameplay in your basic Kingsburg. However, the game offers little excitment when compared to 4 or even 3 players.

Just don't forget to roll the "nuetral" dice before each production season to ensure it remains balanced, and strategically wise always gun for the Envoy with the resource count as a tiebreaker (which is much easier to do with a 2 player game).

I've never played Kingsburg with two players.  We actually discussed this very topic at my game group over the weekend.  At the time, there were only two of us, and we considered playing a two player game of Kingsburg.  However, we decided against it because we didn't think it would be very challenging or as interesting with only two players.  There wouldn't be as much competition for resources, making it much easier for players to get the resources they would need to build every turn.  With 3, 4, or 5 players, there is much more competition over resources, making how and the order in which you place that much more important.  I feel this is one of the things that really adds to the game.  Placement can really be a balancing act with more players, because you got to think, if I influence this advisor, are the others still going to be available to me by the time it gets around to me again.  Sometimes, your placement is more about beating the other player there, rather than actually needing the resources or benefits that that advisor offers.