There are lot of differences b/w viruoso and virtuoso-XL.
Virtuoso-XL is connectivity drivn, where in your layout is created from schematic, at the same time you can cross-highlight and probe the nets/devices/pins b/w sch and layout.
It has advanced features such as Tx Chaining and Folding.
Cloning -- copying with connectivity.
ECO changes
and many more...