Here are some things you should expect for the remainder of season 3. 

    • NOTE** I have gotten these theories from trailers, news, etc. I am not putting in spoilers. 

Darryl lives, Merle is unknown (I got this from the preview right after episode 8, this is not a spoiler at all)

Andrea goes good - she is scene holding a blade or knife or some sharp object while standing over a sleeping Philip. 

Rick and Philip will meet (hence the very latest trailer)

One more person will come in according to Kirkman - My guess is Morgan, check this blog for another theory. 

Milton and Philip will have a 'bumpy' relationship according to Milton's actor. 

Tyreese will step up. 

Ben and Allen will try and take over the prison. 

Rick will lead the 'army' down to Woodbury. 

Carol will use a human shield in an attack. 

Philip will show his dark side to Andrea, telling her "If you go to that prison, YOU STAY THERE." 

Andrea will stop by the prison. 

Glenn will talk to Andrea and convince her that their gonna fight Woodbury. 

Rick and Michonne - possibly Carl - will go on a 'trip' somewhere. 

Hershel will even fight. 

Beth is not scene in the fight, so she will most likely tend to Judith. 

Darryl will find someone with a baby in a car, the car surrounded by walkers. 

Andrea will try to stop Philip from making Darryl and Merle fight to the death. 

Merle will throw a punch at Darryl, it is unknown if they really fight or if he is distracting Philip so someone - Rick? - can save them. 

And... There is a firetruck that breaks through a fence...

I will update this as more previews, promos, and trailers come out.