Well, technically, the birther debate could even continue to haunt Trump. The hardliners approach is that it doesn't matter if Obama has a Hawaii BC because the father was a Kenyan national and their interpretation of the constitution is that a President has to be a "natural born" American citizen-- meaning both parents have to have been born in the US. This issues has, of course, been spoken to by the Supreme Court through the years but it keeps raising it's head...... of course, Trump's a white guy so it's doubtful they will chase him down the path with torches but you never know....
I think the fact that Trump is not going to ever declare his candidacy will remove any hunt for the Trump birth certificate. I think he is using these presidential hints as a way to promote his show. After it completes it's run, we won't hear a thing about Trump the candidate again.
The weird thing is that the Republican field is so weak that Trumps points about China were actually wearing pretty well. He almost could be a legit candidate if he stuck with that, but the birther stuff gets more publicity, which is why I think his candidacy is merely promotion for his show.