LKH mentions Richard smelling things, and being faster and stronger and allround better for being a werewolf. This would suggest that the physiology completely changes when a person is infected.
I've seen seeing in the dark mentioned in fanfic as well, but I'm not sure if this is fanon.
Of course different animals would probably have different effects, but I'm thinking more of the leopards and wolves here.
Irving wears glasses.
Opinions please :).