Well, we have a shower curtain (white lace) covering our shower doors in one bathroom. (Full size shower...tub-size, but no tub.) You can sort of see into the shower, but it is FAR prettier with the curtain. DH likes the shower curtain closed while he showers (glass doors), but tends to leave it open after he gets out. I like the shower curtain partially open while I shower and much prefer it closed the rest of the time. (I can see out for little ones, but I cannot read the clock if the curtain is closed.) Works great if DH showers first!
The other bathroom has a tub/shower and we pulled out the shower doors a long time ago because I hated cleaning the bathtub with the tracks and being pregnant and knowing it'd be just as much of a pain once the baby was here. When anyone comes up the last set of stairs, this tub/shower is the first thing they see. I prefer they (we) see a pretty shower curtain than the boring shower surround. DD only has one shampoo and one conditioner in sight, so I don't care about that. More important to me than the visual appeal, though, is I don't want mildew growing on the liner.