There will be multiple instances of Cyrodiil. We are going to work with a campaign system where the same players play in an instance of Cyrodiil until certain marks are met by one faction. Dailies are here for a lot of the PvE players. Unfortunately, this is one of our only end game components for PvE. Other than that you are correct, all we have are heroic dungeon runs. Adventure zones won't make launch.
You can change between campaigns for an ingame PvP currency fee (internal testing), we are also weighing the option of allowing someone to join someone on their friends list for a day without a fee, but they will be sent back to their own instance of Cyrodill after playing. Either way, this doesn't do much for either player other than they can be together in the same instance for a time. And really, there is no reason to even play this content other than a dick-wave. Nothing that happens in Cyrodil will have any impact on the player's home PvE base. Completely separate worlds, and it makes the entire experience feel fake. We have brought this up many times, but without any budgeting going to our area, we have no choice but to shoe-horn in what we can to ship this thing out in April.
With that said, you can have multiple campaigns running at the same time so you will be able to hop between them all. This is the only end game content that will be in the game. Most assets are tied up polishing 1-20, as we are so far behind. And we all know where those assets are going and why we are behind to begin with. Where is Rich Lamberts promotion when you need it? Paul Sage is incompetent. And it is holding back assets from the rest of the game. We are having major issues with animation/UI control/links and responsiveness, ability tail off and bloat with trait design... As of right now this is probably the worst project I have ever been on in my ** years in the industry.