Is 1940s Style the New Black?

So I have noticed something in the last few days. Something that may shape the way we shop for next season. Of course we all know that the '70s are back for this winter and into next summer, but what decade is nipping that their heels? Well, it seems to be the war-time '40s.
The new West End play that Sienna Miller is killing it in at the moment is set in that time period and the tabloid are lapping up her style in the show. Also, this past weekend, actress (and ex of Marilyn Manson) Evan Rachel Wood turned up to her latest premier in this burgundy number that I think looks staggeringly beautiful.
A small diamante brooch here or there. A kiss curl in your hair and a little bit of elegance will be the necessary ingredients to achieve this style - time to start practicing, I think.