As this doesn't really fit as a rumour and the Idoneth Deppkin are discussed elsewhere, I'll leave this here for you:
Breaking News: Major Reveals - Warhammer CommunityThoughts:
1. That new knight looks epic. Literally, it looks like an epic Warlord Titan, just a bit curvier. I think it looks brilliant and, with the addition of the Armigers, maybe makes a knight army feasible...
2...which we'll find out soon enough, given the next 3 Codexes. Good to see Harlequins hit and it's also great that the next 3 books cover more niche armies. Even the power armoured variety are niche.
3. Power levels only for the army builder app. Meh.
4. Sounds like they're trying to get them right so that they are worth the wait. Still, exciting that they've finally listened to the fanbase and they're doing something about it. Fingers crossed they're awesome!