Lots of love for X.
For me, once again, my top Def Leppard albums are
1 - Euphoria
2 - X
3 - Hysteria
The song GO is one of their best songs ever, however.
So, if the new album is anywhere between what Andrew said, like Euphoria and X with a hint of Hysteria, it is possible it becomes the top or second album.
Anyway, if it's anything around the top three, it'll be a great album.