I’m watching Glee, along 13.7 million other people, give or take.  

I was pleased by the rehabilitation of Britney Spears.  I mean, why not give her a chance?

Mr. Schuester doesn’t want to.  He wants to feature Christopher Cross.  The kids think this is a deliriously stupid idea. They grew up with Britney.  

If we didn’t know any better, we might suppose this is show making sly fun of American Idol. Christopher Cross is just the kind of person American Idol would like to feature.  We could be forgiven guessing that most of the musical programming is being done by Elizabeth Taylor.

Britney on American Idol.  Never!

Things get even better when Rachel (Lea Michele) comes out of her dentist-induced anesthesia and says, "is this real life?"

This is a reference to the YouTube video of the little boy coming home from the dentist.  he was filmed by his Dad as he "manfully" trying to sort out reality from the effects of sodium pentothal in the back seat of the family sedan.

This is Glee referencing not only the full scope of popular music, but the fuller scope of popular culture.  Indeed, this is popular culture aiming for complete self sufficiency.