This card seems hard to evaluate now, even when I'm ignoring the new set.
Trying anyway:
* The main use for this card is in BM-draw-ish decks that are looking for their 5th / 6th province to seal the deal. It's super powerful in courtyard-BM that fights an engine, although you want only one.
* It has a lot to do with reshuffles. You don't need to spend that coin now, but you do need to spend it before your next shuffle.
* It has quite an impact on the endgame. Duchy dancing fine with me, especially if I'm building towards double province.