LOL! It's almost three years since A Dance with Dragons was released. Before that, it had been six years since A Feast for Crows was published. And there was a five year gap between AFFC and the third book in the series, A Storm of Swords.
I think we may still be waiting a little while for The Winds of Winter. Although I do get the sense that the HBO series may have lit a fire under George R.R. Martin's ass. I do get the sense that TWoW is going to be released before the HBO series catches up with the books. But I'm not as optimistic about that happening with A Dream of Spring.