FreeviewPlus is now called Freeview On Demand, nothing has changed except or the name! 

Explore a new way to catch up on a guide that allows you go back 8 days, tailor the latest TV Shows and Movies and live listings together. 

Catchup apps are available for TVNZ On Demand, Three Now and Maori TV On Demand so you can stream to your heart's content. However to get On Demand you will need an approved Freeview product or TV that has "FreeviewPlus" or "Freeview On Demand" and a broadband internet connection.

You can check out more info here at http://freeviewnz.tv/freeview/on-demand/