Most of the teams showed up to race with some kind of variation on the "drag sled" using a traditional "drag line." You can see why Aliy's dad said the line is a trip hazard!
A few teams are using these "Dual Position" or "Tandem" (or whatever they're called) sleds. I've most often seen them used by a single musher who wants to have the option of riding in the middle seat or "pumping/poling" in the back. Obviously, two people can use it instead.
As with the SP Kennel "star trek truss" innovation, a few teams brought their own new designs. Here's one that I would call a "hard mount with flex."
Here's a sled with three runners on the bottom.
"Why?" you ask?... Well, because it's a double wide!
That about covers the sled configurations for the race. I'm not going to try to explain pros and cons because it would all be speculation at this time. Maybe after the race we can get some reports from the mushers about how their sleds worked out for them!