At the end of last year, NBC and Apple were struggling with each other over NBC's shows on iTunes. It ultimately ended up with NBC leaving iTunes and launching their own video site. The loss of NBC was a blow to Apple, as they were the largest single provider of video content for the service.
Time has apparently healed NBC's wounds, and following up on their intentions earlier this year to rejoin the Apple fold, NBC shows are once again available on the site. Apple is now selling NBC shows and, once again, they have kept the $1.99 price tag that was originally upsetting NBC so much. They didn't keep the price tag for HD content, which now goes for $2.99 per episode.
It isn't mentioned how much price flexibility Apple will let them have on iTunes, nor if they plan to cave to other NBC demands such as more anti-piracy measures.