This is the same version of the standard used for the DITA 1.2 Public Review. Release 1.5.1 contains many fixes and minor enhancements. It also includes a preview of a new output transform to the Open Document Format; this transform will be completed in a later release.
Release 1.5.1 was developed using a series of test builds released to the community every three weeks. Each item in the list below indicates which test build first contained the update. There were seven total test builds.