In an Interview with id`s Community Manager Peter Sokal on Bethesda Blog, chief of the Quake Live Team Marty Stratton talked about the premium service.

Is he talking about "private server" = private match on demand, configurable through quake live site?
And what did "content" mean, maps perhaps?

Marty:
We’re toying with a number of ideas for features, functionality, and even content that will translate well and represent a real value for players wanting an affordably-priced premium service. One of the most requested features in QUAKE LIVE and something that I think would be at the core of any premium service, would be the ability to very easily and quickly start a private match (that only you and the players you invite can join). Right now, all of our matches are open to the public and started by our back end systems. So, what we’re looking at creating is a totally integrated and very easy to use method for starting and running a personalized private match.

It’s a similar concept to players in other games renting their own server, but our approach would be to allow them more of a “private match on demand.” Making this type of system available through the same site you are playing the game on, allows us much more flexibility in making the interface easy to use and more integrated with things like your friends list.