"My goal was to mislead the audience into thinking Kara Thrace was a Cylon," Eick said. Being a Cylon, after all, would mean that there were many copies of her, and therefore Sackhoff could come back as a different version of Starbuck.
DE's words pretty much makes it official that Starbuck is not a cylon, thus closing the door on the only logical explanation for Starbuck's return IMHO. Also it's been stressed many times in the article that Starbuck the character will return, not just the actress who plays her. To me this can only mean Starbuck is morphing from her Top Gun-ish character into a Superman-ish character.
But what bothered me the most is the callous way RDM and DE played with fans emotions. Why are they so hell-bent on tricking the viewers? As a good story-teller, don't they want the viewers' understandings instead?!