I love playing "guess-the-sex". Since no one has replied yet, I Sam's going to guess pullet based on no saddle feathers and rounded tail feathers. I am very much a newbie though, so am eager to hear what the experts say.
Yup hen. I have a RIR with a very large comb and I named her Charlie just because her comb is more masculine than the other RIR's. However Big Red has a HUGE comb and he is very obviously male. Even at a younger age, the tail and saddle feathers do give them away.