There is a floor and a staircase within the spire but it is only going to be used for maintenance and nothing else. Plus thanks to Otie we can see inside the spire.
And no there will not be a 2,000 footer in New York at least not anytime soon. Plus this building can't go to 2,000 feet. In architecture and engineering you learn that a building can only be designed to reach a specific height once started, and construction is almost done so the design or the height can't be changed. Except for the spire which Durst is trying to do, but people don't really like it and are protesting about it.