Hopefully the vault has some treats to offer up. Always lovely to hear Nina's voice, though her recent projects have not grabbed me.
It just feels inevitable, because as you pointed out, they still tour. Eventually they'll get tired of playing the old songs, start fiddling and maybe we'll get something out of it. Look at ABBA - Anni-Frid and Agnetha sangt at a Mamma Mia event, which then led them talking about doing something to celebrate ABBA, then they started working on a tv special, which then turned into them recording two songs, which then snowballed into ABBA Voyage and a full album.I wouldn't count it out. They still tour (and an interesting reply on that FB thread is that they would love to tour the UK but no promoter seems interested...) and are therefore on good terms. I can see them having a reunion at some point, though, yes, Nina seems to be interested in other projects right now.