Zach and Miri Make a Porno (2008)

The film starts out badly; the opening scenes in their apartment, going to work, at work, and going to the HS reunion are uncomically dreadfully written and Rogen and Banks can't elevate the material.  I was ready to shut it off, but then the character of Brandon appears at the reunion and everything suddenly starts to click.  Justin Long saves this movie with a cameo!

In the scene where Zach and Miri "do it" for the first time, Smith does a good job of showing the difference between the experience for the people "making love" and the experience the people watching, and contrasting that with prior scenes showing people simply "having sex" for the camera.

Whoever selected the soundtrack deserves some praise; Fett's Vette is a perfect choice during the "Star Whores" montage, and the sequence where Blondie's "Dreaming" is followed by a clip of DMX's "Party Up" (while they're dancing at the cast party), followed by the Pixies' "Hey" (as the party is winding down) is inspired.  Moreover, as Zack and Stacey go back to his room, the pacing, staging, and look on Elizabeth Banks' face perfectly wrap up this section of the story.