Here's a quick recap of the NBC/Apple tussle, for those who are tuning in late:

NBC says Apple is mean and won't renew their contract ('These shows are my toys and I'm going home!').
Apple says NBC is a stupidhead, and NBC's shiny new shows won't be available in iTunes ('How are those toys now? Taste a little better with the salt from your tears, NBC?').
NBC and Amazon become BFF's. NBC no longer makes eye contact with Apple when they meet in the hallway between classes.

...

NBC went with Amazon, reports the New York Times, because Amazon agreed to be flexible with pricing. This translates to higher prices for more recent shows, with the back catalog being cheaper (which is what I assume NBC wanted Apple to do all along).