Cyrodiil will have the large scale 100vs100 Open PvP (Simmilar to WvW in GW 2 just not WvW) but they also stated there will be "competetive PvP" i assume thats something along the lines of battlegrounds.
Mmhm, I can't remember the wording, but it's all but confirmed that we'll have instanced PvP in the game as well. Can't say I mind, though I hope to see more than your standard TDM, and CTF modes, make an apperance.