A 30-second ad on NBC's "Sunday Night Football" runs a cool $339,700, on average, according to an Ad age survey, making it the most-expensive fall program for advertisers. The next nine slots are made up of scripted shows, with a 30-second spot on "Grey's Anatomy" costing an average of $240,462, while a 30-second ad on "Desperate Housewives" running an average of $228,851. All these numbers are significantly lower than a year ago, according to Ad Age. Meanwhile, "American Idol" ads are going for between $360,000 and $490,000.

The figures should be taken as directional indicators, not gospel. The estimates are based on what advertisers paid for ad time during the recent upfront market, during which marketers commit to pay for predetermined amounts of ad inventory months or weeks in advance in exchange for locking down price guarantees.

Already, the market has noticed that prices for scatter inventory, or ad time purchased much closer to air, is up "mid-to-high single" percentages above upfront prices, according to Wells Fargo Securities. That's good news for TV broadcasters, but not such good news for marketers readying holiday-season ads. Broadcasters held back, on average, 10% to 15% of time normally sold in the upfront, betting that they'd command higher scatter prices.