Ability to create Region metadata
By specifying the regions field in DXA Page Template metadata, you can specify Region metadata.
Having Region metadata enables you to predefine Regions on the Page Template level, which in turn enables you to have empty Regions in your Page Model. (The new Html.DxaRegion method also includes an emptyViewName parameter for this purpose.)
By default, the regions field allows you to specify a qualified Region View name (the Region name is always the same as the unqualified Region View name). However, because DXA uses an embedded Schema for the Region metadata, you can also define additional Region metadata, to e used by a model builder extension, such as the SmartTarget module.