It wasn't part of 7.x nor it is part of 8.x. I wouldn't see it as part of the phone operating system at all. IMHO it doesn't belong there. Modern phones get their power mostly out of the overwhelming number of applications available.
Nokia is indeed hard working to separate their phones from other Windows Phones, so there is an app called Nokia Transit/Transport available to provide information about public transportation. Also, they do provide some basic information using their map solution on here.net.
Some local public transport services offer their own app, so you could do a search in the store.