[warning: deductive reasoning applied here]
The release (through PR) of these promo images [Nos. 5,6,7,8, 10 below] let us make some deductions about what we'll see in Daybreak, Pt. II. First, we know we'll see some kind of big space battle (one which is totally unnecessary, mind you, if Cavil had only guarded the Hub better ... but, hey, this show needs a whiz-bang ending). We know HybridSam will make that perfect throw. We know Roslin probably finally dies, perhaps alone on the Galactica - having been forgotten or left behind (or it's a fake-out and someone takes her on a Raider). From other promo images floating around (in some cases for months) We know that Cavil, Simons, Dorals (and probably inhibitor-chipped Centurions) board the Galactica. The only reason they would do this is to kidnap Ellen and/or the Final Fivers for their resurrection knowledge or to retrieve Hera again for her secrets to resurrection and Cylon survival if she had been rescued and returned to the dying Galactica (which Cavil wouldn't need if only he'd protected the Hub). Third option is that Cavil sends extra models of himself and the 4s and 5s to finish the old rust-bucket off for the sheer joy of it.
We know that Caprica Six decides to stay with Baltar and fight (ah, can't you just hear Reunited and it feels so good ...?). People in the C&C are looking up: is something on dradis? Is Cavil or somebody in the upper tier? We know Helo gets a severe injury and probably dies (at last ... can't they splatter Hot Dog already while they're at it?).
Some smallish craft jumps in or out from between the attacking Cavil forces and the Galactica. And in the biggest reveal so far the Final Fivers (except Sam - who is stuck in the Galactica version of a Goo tank) and Boomer stand around something in The Colony. The supports behind the actors and the larger scale of the room allude to it being not on a Base Ship so it must be in The Colony. This is probably the big reveal scene/info-dump. It could be the remains of Daniel lying there in that tank as he gurgles out answers, looking kind of like this maybe. The FFourers look kinda sad, so I guess it's not good news. Our big grand story is probably going to boil down to Goo-Daniel, or some other higher power, telling them all that they are abominations and should all die and never recreate robots or resurrection technology again.
Cavil won't like this and has kept Daniel alive to torment him and now seeks to rub Ellen's nose in the suffering - or Cylons are a very ancient race and morphed many times and we'll hear from an ancient Cylon "god" delivering the same message. Cavil goes nuts, tries to kill the higher power and is destroyed (perhaps Hera interfaces or has her eyes read by a Centurion and directs them to revolt). Moore is throwing buckets of cold water on the Daniel angle, and if he's telling the truth then the Daniel thing has been an epic fail - a horrific retcon.
As I've pointed out on the SciFi message boards there was no need for a Daniel character to be introduced at all. Ellen could have just said, "I like the number seven and kept if for myself," and no character, nor the audience, would have questioned it - she's a floozy boozy whackjob when she's not CylonMotherGodWhoKnowsAll - the numbering problem solved.
Our survivors of course limp off to real Earth. Groovy. Then the issue becomes when?