• by David Goetzl  @dgoetzl, March 21, 2008

Does product placement work--does it ring the cash register? Despite a seemingly endless run of studies and different metrics developed, it's apparently about as hard to divine as whether it will be Obama or Clinton.

P&G CEO A.G. Lafley has indicated that a new research concoction known as P.R.I.S.M. will offer scientific evidence about the effectiveness of in-store promotions--whether, say, a Prilosec display at the front will lead to a purchase in the heartburn aisle. But Even if P.R.I.S.M. proves to "transform" marketing analysis, as Lafley said it would, nothing as promising would seem to be on the horizon in branded entertainment.

Absent that, anecdotal evidence might provide some insight. And two recent examples offer the potential for contrasting conclusions.

In one, a marketer seems to be satisfied enough that it's using the show for a second straight season. But in another, an advertiser not only didn't renew, it ceded the branded entertainment turf to a competitor.

First, the contented: Wrigley believes it has significant growth potential by convincing people that gnawing on a stick of gum is a weight loss ally. Evidence is spotty, but the gum-maker has created a Wrigley Science Institute to examine the topic and fund studies revealing that--shocker--gum can indeed serve as an appetite suppressant.

Last fall it took the message to NBC's weight-loss competition "The Biggest Loser." In one episode, trainer Jillian Michaels acted as if she had a doctorate from Wrigley Science. As contestants prepared a meal with the temptation to snack on the ingredients, Michaels told them: avoid the nibbles, chew a piece of gum. "My favorite is Wrigley's Extra Supermint," she adds.

Fast-forward: Wrigley appears to have been pleased enough with the results that it's re-upped and is now back on the current season with the same pitch: gum-chewing leads to pound-shedding. On the March 4 episode, the host displays a pack of Extra sugar-free as if it were the Hope Diamond, then hammers home what Wrigley hopes will become a memorable magic number: 5 calories (per stick).

The episode then includes a challenge for the contestants with Extra as a focal point. With that comes multiple brand shots, including a panorama of the multiple flavors.

Contrast Wrigley's return with Pontiac's shift to the sidelines. A year ago, the automaker sponsored the premiere of FX's underrated drama "Dirt," where Courteney Cox plays tabloid editor Lucy Spiller. And the company's new Solstice convertible made an appearance as Spiller's car of choice.

The Pontiac relationship was quite a maneuver, with Cox offering up the following valentine at the debut's end: "The entire cast and crew would like to thank everyone at Pontiac for presenting tonight's premiere episode commercial-free."

But Pontiac took a pass this time around.

"Dirt's" second-season premiere on March 2 was sponsored by Audi, which looked to plug its new R8 roadster--also the subject of the well-received "Godfather"-spoof Super Bowl spot. The Audi sponsorship included two "presented by" billboards, while the car played a prominent role in an extended heart-throbbing scene within the show.

There, Spiller zooms after a celebrity subject for a prized photo. (Both the Extra and Audi appearances were two of the top product placements of the week, according to measurement firm iTVX).

In the show, FX has Spiller Andretti take the R8 through the L.A. streets. On display are the sweet hum of the engine; the explosive speed that would seem to allow for zero-to-60 in like zero; tremendous handle on a blazing turn; and more sparklers--all as the camera offers shots from multiple angles.

It's difficult not to covet one of the R8s (perhaps until the $109,000 price tag becomes apparent).

Wrigley has stuck by the "Biggest Loser." Even after it was panned last year, FX stuck by "Dirt." Will Audi do the same? One thing is clear: A decision will have to be made without any surefire effectiveness R8-ing.