Nielsen’s new methodology to compile data that take into account viewing of commercials that run in a particular show, online or off, could be in place by September so it can be used for ad sales in February 2011.  “If this system were adopted en masse — and it’s not clear that it would be — online viewing might be crammed just as full of commercials as the more traditional TV-watching experience,” Ad Age says.

And, while online sites like Hulu and Disney’s ABC.com typically have few ads, “many TV executives say these methods don’t bring much, if any, profit — and therefore cannot continue.”