Jeremy Hobson: Facebook holds its developer’s conference today in San Francisco. It’s planning some changes to its site, in addition to the ones that it unveiled yesterday — to a not-so-great reception.

And as Jennifer Collins reports, those changes may seem small compared to what’s coming.

Jennifer Collins: Media consultant Ted Cohen says Facebook’s about to let you and your friends share music more easily.

Ted Cohen: If I see that a friend of mine is listening to the Chili Peppers on Spotify.

Spotify is a music subscription service.

Cohen: And I have Spotify, it’s going to let me hear the Chili Peppers on my Spotify account.

In Facebook. Cohen thinks soon you’ll be able to listen to any band on any service and watch TV shows and movies friends recommend too.

Lucy Hood is with the USC Marshall School of Business.

Lucy Hood: It’s the ultimate killer app: What I want, when and where I want it.

That’s good for Facebook because the social network would then have you where it wants you when it wants for advertisers. And for the media companies, Cohen says:

Cohen: For people who haven’t subscribed to any of these services, the path to listening to a song.

And potentially signing up as a subscriber.

Cohen: Is a very short walk.

That is, if they can get past the usual user revolt.

I’m Jennifer Collins for Marketplace.