Instead, a new host of daemons greet us, with new plaguebearers, nurglings, blue scribes, flamers and a big Slaaneshi chariot. The nurglings in particular look great. One hears a pamphlet will be released to update both the daemon army book and codex, exciting news for daemon players. Here's a video on the new update.
The images below are via Dice and Brush.