//metasave and //metaload are now superceded by //save and //load's new functionality. worldedit.deserialize now supports every version of the WorldEdit format that has ever existed, and the new worldedit.valueversion uses file characteristics to determine which type of file format a given file uses. The new WorldEdit file format is the same as the one used by MineTest for serializing data, and is capable of storing arbitrary data, as well as leaving fields for future improvements. In other words, this is the last forward-compatibility breaking change that will be made to the file format.