The network will air the 36 eight-minute episodes of the Web series, which premiered on MySpace.com Nov. 11, as a six-episode hour-long drama.
"This is really a new form that doesn't pertain to any other series or program out there, "Herskovitz said.
Quarterlife will have a smooth transition to the small screen, because it was conceived as six one-hour story arcs that were then broken into six webisodes each.
"I've been writing one-hour stories for 34 years, I know how to that," said Herskovitz, who along with Zwick, created such cult classics as thirtysomething, My So-Called Life and Once & Again.
Quarterlife will get a second window on NBC in early 2008 after it concludes its run on the Internet. It will also be streamed on nbc.com.
"Ed and Marshall are well-respected TV veterans that repeatedly have demonstrated a creative voice that resonates with a wide audience," said NBC programming chief Ben Silverman. "'Quarterlife' is yet another show that evokes their renowned storytelling skills and but is based on an innovative, new business model."
In addition to broadcast and online, NBC is also getting DVD and foreign distribution rights to Quarterlife as well as an equity stake in quarterlife.com, the show's companion social network site that also posts Quarterlife episodes a day after their premiere on MySpace. Herskovitz and Zwick will retain 100% ownership and creative control of the series.