That is a Nephila sp tropical orbweaver. They're often called Golden Silk Orbweavers because of the gold color of their silk. We have a species (N. clavipes) in the southeast United States, from Florida to Texas.

http://en.wikipedia.org/wiki/Golden_silk...

The abdomen looks pretty hard done by but the body (exc. legs) looks like it's just over 1.5 inches, need some help identifying