Late-night network shows are suddenly in hot demand of national TV advertisers.

"We've been seeing double-digit price increases over upfront pricing," says Chris Simon, executive vice president of advertising sales for CBS, for the "Late Show with David Letterman" and "Late Late Show with Craig Ferguson."

Simon says active advertisers include automotives, consumer electronics, and pharmaceuticals. Among all categories, Simon says, he is emboldened that financial services TV marketers have also been making a comeback.

Overall, "it's a very nice vote for the daypart -- especially for us at CBS," adds Simon. "Marketers are starting to feel a little bit better about how we are as a country."

Media buyers also say NBC is completely sold out of its inventory in "The Tonight Show with Conan O'Brien" and "Late Night with Jimmy Fallon." An NBC spokeswoman would not comment.

"It's really hot; virtually everyone is sold out," says Ira Berger, director of national broadcast for the Dallas-based The Richards Group, says of the time period.

Much of NBC's gains may have to do with the network giving back some makegood inventory to marketers. For example, O'Brien is down 22% among 18-49 viewers for the first four weeks of the season; "Late Night with Jimmy Fallon" is down 16% in 18-49 viewers.

Both CBS's late shows have seen about flat viewership against a similar time frame a year ago. But CBS' "Late Show" can now be found to beat or tie "The Tonight Show" among key 18-49 viewers -- something it wasn't able to do when Jay Leno hosted the show for virtually the entire run of the program.

The Letterman scandal has had virtually no negative effect among advertisers, according to media buyers. Media buyers also say an overall lowering of late-night ratings points could be creating a favorable supply and demand situation for the networks.

Media executives also note that ABC's "Nightline" and "Jimmy Kimmel Live" are seeing pricing benefits. Pricing for big late-night shows such as those hosted by Conan O'Brien and David Letterman can command $45,000 to $55,000 per 30-second commercial.

Gary Carr, senior vp and executive director of national broadcast for media agency TargetCast TCM, says some of the shift of advertising dollars into the daypart could be from national advertisers holding back money in the first half of the year or from summertime's upfront process.

Similarly, network prime-time scatter pricing is higher than the upfront marketplace deals. Jo Ann Ross, president of advertising sales for CBS, says scatter prime-time pricing is seeing double-digit percentage CPM (cost per thousand viewers) increases.

With only four weeks of the season so far, CBS and Fox are two networks that have witnessed better results versus other networks -- thus grabbing scatter money might be less problematic. "For us, it's a little bit easier, because our numbers are good," says Ross.

A General Electric executive said during a recent earnings call that scatter pricing on the NBC network was 10% higher than during the upfront selling period and 20% higher on NBC Universal's cable networks.

As with late night, media buyers say some of this is misleading, since NBC's primetime prices for selective inventory could be boosted by giving away commercial time to TV marketers for shortfalls in promised in upfront advertising deals.

One veteran media agency executive says of TV marketers moving now: "There is a tremendous amount of pressure to show growth in the fourth quarter for most companies-- not bottom-line growth, but top-line."

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