LOVE Callie and Arizona - definitely made for each other. And Shonda Rhimes has said that the break-up is 'just a blip in their relationship'. :oD
So here's a possible finale storyline: Callie gets shot, almost dies, and Arizona is distraught and realises she can't live without her. Because of the shooting Callie can no longer have kids and is devastated, so Arizona decides to carry instead. This would tie in with JCap's real-life pregnancy...
Well we can dream, can't we?!