Whats the big difference between the motorola xoom 3.0 and 3.1?

[Toni]

Heya is there much of a difference betweeen the motorola xoom 3.0 and 3.1 android, im pretty clueless when it comes to this stuff Also why does the motorola xoom have a sim card slot?? Can you use your phone sim card in it or what?
Thanks a million for any answers really appreciate it. (",)