What is the difference between the John Deere X570 and X580?

Here is how the John Deere X570 and John Deere X580 compare on John Deere's published specifications:

• Wheelbase: John Deere X570 51.2 in. vs John Deere X580 51.2 in.
• Cutting width: John Deere X570 54 in. vs John Deere X580 54 in.