Most Helpful Girl
I'm off to buy that dress now.
Anyway - as for your arms, I'd probably go with a black, boyfriend fit blazer. Emphasis on the boyfriend fit, a short or normal blazer will separate your body - and the dress already does that; and I think it would make it look too 'formal' - boyfriend fit is far more chic - at least I think so.
I think that's the only thing that will really work with the dress - a cardigan, however nice, would make it ... it would just cheapen it I think. And anything else - like those sheer cover-ups or something like that would detract attention from the dress. You really want the dress to be the statement.