Hi, just a note to warn you, in the case you're interested in LadyAda XBee adapter for an XBee-pro module.
They're advertized as being compatible but that's not really the case. The PRO modules have a longer tail that goes over the capacitor in the bottom, which prevent placing the module at all.
The guide says: "Make sure the capacitor and regulator sit close to the PCB, especially if you're planning to use an XBee Pro module". Unluckly, that's not enought.