luas line d

this is probably a silly question, but what is happening with luas line d, i was just reading the dit grangegorman bumph and they mention it, dcu and ballymun are obviously keen as well. at some stage someone had the good idea of connecting it to the tallagh line at smithfield, it would certainly be an easy way to improve access to the airport and would do wonders for various places along the way. have we stopped thinking about it or are people trying to partch together a ppp behind the scenes.