There has actually been some progress on integrating GTFS data into OSM: https://wiki.openstreetmap.org/wiki/GTFS

I haven’t yet seen much use of it in the wild though…

Isn’t one hurdle to integrate gtfs data into osm based apps the fact that there is no reliable way to link osm nodes with gtfs nodes? How did they get around that?

Does this mean that access to real time arrival data is on the horizon for osm based apps?

Edit: It appears that a lot has happened since I last checked, how cool!

Reference: https://wiki.openstreetmap.org/wiki/GTFS