Yes you can to a point. The first wing feathers pretty much look the same, the body feathers are different. Like Frazz said though even that is wierd sometimes. Iv'e hatched quite a few of both sexes and if I had to say right now i'd say female, we will see if i'm right.
I guess I'll wait. I read on Feathersite that they can be accurately sexed from 10 days, by the colour of their feathers. Is that true?