From nytimes.com:

In the world of broadcasting, PBS shuns commercials. On the Internet, things are different.

The publicly supported, not-for-profit television network just announced a deal for several programs to be streamed on the Hulu Web site. These include “Nova,” “Wired Science,” “Carrier” and “Scientific American Frontiers.”

Hulu will place a 30-second advertisement before each program, splitting the revenue with PBS. Andrew Russell, the senior vice president who runs PBS Ventures, the network’s money-making arm, said the company is trying to balance its need for revenue with its noncommercial heritage.

“It is very important to carry the principles of public television into these environments,” he said. Most significantly, he said the network will allow commercials only at the beginning of its shows.

“We do not allow interruption of our programs,” he said. Also, it won’t allow the companies to sell commercials on its programs to certain types of advertisers, such as tobacco companies or politicians.

Mr. Russell said PBS is looking for any complaints from viewers. It hasn’t heard any, but the program is new.

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