Marty Noble at Mets.com writes about the Home Run Apple and that it could be included in the Citifield Plans:
The Mets' new home next season may have a piece of their current home -- the Apple. No matter what, a home run apple will be installed just beyond the outfield wall -- as it is at Shea Stadium -- but this one will be left of center. And according to Mets COO Jeff Wilpon, it hasn't yet been determined whether the old one can handle the move or whether a replacement will be necessary.
That would be great if it could. I know that it is out dated and that it is an eye sore, but it holds sentimental value for us Met fans.