Using XML to transfer in/out of FCP

A quick reference for which version of XML to use when transfering between FCP project file versions:

XML / FCP version Compatibility
Use XML version 1 for going to Final Cut Pro 4.1
Use XML version 2 for going to Final Cut Pro 5.0
Use XML version 3 for going to Final Cut Pro 5.1.2
Use XML version 4 for going to Final Cut Pro 6

Thanks to Kenstone.net for the tip