Upgrade: Noun. An improved or more modern version of something.

Recently separated Sean Penn was seen hitting the Oscar circuit this weekend with model Petra Nemcova on his arm. Now I can't speak for Sean, but considering that Petra was most recently romantically linked with James Blunt -- this is a huge upgrade. Of course, if stupid James Blunt was your last boyfriend, a chimpanzee wearing a tuxedo and soiled diaper would probably be considered a vast improvement.