Don't know if it's just me or not but stealing seems to be much easier in Skyrim. I remember getting caught even when no one was looking in Oblivion but I can simply be ducked behind a counter in Skyrim and easily rob a shop blind. The other day though I had a couple mercenaries after me and after dispatching them found a letter ordering my elimination by someone I had stolen from in Whiterun. I wonder if this is just a part of the story line or is this the effect of my criminal activity?
Just put baskets/buckets over their heads and they will see nothing. (Just to be safe also all the animals should have buckets on their heads too)
In skyrim the detection system is line of sight based so if they can't see you then they can detect you. Although there are bugs were you can be detected stealing when there is no one or animal around you for some reason.