A "hide shoulderpiece" option.

Pretty please?
I like transmogrifying in the new patch. It puts emphasis that our characters are strong and not just our gear. Sometimes wearing a dress or shirt looks really bad with shoulders..

At least for now, there are no plans to make other slots 'invisible'. We're starting things slow with the first roll out of Transmogrification, so the feature set has a good chance of expanding in the future.

It's also worth mentioning that shoulder items are highly distinctive, and a lot of effort is invested in making those items look cool and interesting. It's not currently a high priority to hide gear which is so integral to the overall look of World of Warcraft.

Your opinions have been duly noted. Fortunately, even if you can't turn them off, using the Transmogrification option will allow you to choose more aesthetically pleasing shoulders. If you happen to find all the shoulders in the game ugly, then I can't help you.

I understand that there are particular looks which are more minimalistic. Transmogrification isn't being added with the intention of making every conceivable look possible - at least, that's not the current intention. It's being added to provide more--a lot more--customization options. I think it's fair to say that it will achieve that goal admirably.

Let's see how things shake out. =)