There are now multiple versions of the LayerDefinition schema.

All layer definitions from MapGuide versions prior to MapGuide Open Source 1.2 use version 1.0.0. Version 1.1.0 was introduced in MapGuide Open Source 1.2, version 1.2.0 was introduced in MapGuide Open Source 2.0, and version 1.3.0 was introduced in MapGuide Open Source 2.1.

You don't need to use a newer version unless you want to make use of the new features supported by the new versions:

• mapping space line width (v1.2)
• symbol definition support (v1.2)
• elevation settings for KML layers (v1.2)
• ability to hide legend styles (v1.3)
  See http://trac.osgeo.org/mapguide/wiki/MapGuideRfc50

LayerDefinition-1.0.0.xsd - Details
LayerDefinition-1.1.0.xsd - Details
LayerDefinition-1.2.0.xsd - Details
LayerDefinition-1.3.0.xsd - Details