Perhaps this is because many radio stations now have their recently-played tracks listed online. This could be a great service, but not at the expense of letting the listener know what they just heard.
Maybe the "average listener" doesn't care - but I doubt this.
More and more I find frustration in the baby steps taken in the evolution of commercial radio playlists. On the occasion that I hear something of interest - a particularly innovative earworm / hook, production technique, or just a rare gem of a song - I would like to know what it was.
In addition to online playlists there are also an emerging number of means for the listener to take action themselves to identify a song and artist. For example, Shazam was one of the first of several mobile phone apps which enable the listener to input a snippet of the song they are listening to, allowing a service to reference the audio and identify the title and artist of the song. Again, great technology, but there is still a lack of immediacy of having the answer provided without needing to grab your phone, launch an app, wait for a response, trust it's correct...
It could be my lack of emotional attachment to the current charting songs, but I remember a time when you knew what song was number one and which artist performed it.
Now I find the songs are more familiar than I want them to be, though I have no idea what they are called or who's responsible.