Boxing & unboxing is the process of converting a primitive value into an object oriented wrapper class (boxing), or converting a value from an object oriented wrapper class back to the primitive value (unboxing).
The Old Dalaran will stay in Northrend, so yes, mages are going to have 2 portals to dalaran (one to Northrend and one to the Broken Isles)
Dunbeath Castle is located on the east coast of Caithness, 2 kilometres south of Dunbeath, in northern Scotland. Although a castle has stood here since the 15th century, the present building is of mainly 17th-century origin, with 19th-century extensions.