Having found myself totally confused within minutes when I started watching
Baccano, I know that is going to happen with this show, too.
So I have already made a characters/seiyuus page with pics of the characters and their seiyuus, so I can keep everyone straight.
Here's the page. I hope other people may find it useful, too.
First episode airs Thursday night at 1:25 am, Japan time. I think that would be 11:25 am Thursday in New York, 4:25 pm in London.