Look, it doesn't really get any more crystal clear or obvious than this. If you think he's still alive, you're clutching at straws and ignoring what is right in front of you.
No more speculation, no more talk of ret-con and false funerals -- Harvey Dent is officially 100% dead. It comes straight from the mouth of Aaron Eckhart, who revealed his character's fate in no uncertain terms to ComingSoon.net "He is dead as a door nail. He ain't coming back baby!"
And lest you doubt that he knows the mind of Christopher Nolan, well, Eckhart asked him whether Two-Face would ever be coming back. "I asked Chris [Nolan] that question and he goes, "You're dead" before I could even get the question out of my mouth. 'Hey Chris, am I?' 'You're dead!' 'Alright, cool.'" There's no chance it will be rewritten or retconned, as he was never even contracted for a third film. "No, I'm not coming back. I think unfortunately, Heath [Ledger] was supposed to go on and that didn't work out. I'm nobody. I'm a cog. I have no say over this sort of stuff. I'm sure that there's so many other characters that they could whip together. I heard Angelina Jolie was going to be Catwoman or something like that. I thought that was a great idea. I'd like to be in that one."
Having Harvey Dent still be alive would totally take away from the impact of his death at the end of The Dark Knight and it would serve no other purpose at this stage than to satisfay the Dent fanboys who won't accept the character died.
Bane and Catwoman are the focus in this film, Dent/Two-Face is dead, get over it.