@vlross,
Ceili has your perfect answer, if it is actually leaking. Now, leaking doesn't mean the gas is going away, and it doesn't mean the gauge is showing an abnormal decline. It means there is wet gasoline on the pavement, or anywhere else besides inside the tank, lines, etc.
If it is leaking, where is the fuel pooling? Below the tank, under the engine, somewhere between, or what?