Yesterday, Josh analyzed the design choices news outlets have made with their iPad apps. But what about the ad design?

The (free) New York Times app sometimes features a banner ad at the bottom of its screen, bigger display ads on article pages, and occasional interstitials when you want to read an article. The USA Today app features a small display on its homepage, with no ads on its article pages. The NPR app features sponsorship messages at the bottom of the screen, which link to audio messages just like you’d head on “All Things Considered.” In other words, for the most part, the ads featured on the news apps unveiled this weekend are familiar infrastructural carryovers, from either the web or the news org’s native medium.

One exception we noticed: The Wall Street Journal’s news app, which puts a more dynamic spin on traditional approaches to online advertising.

The app makes rather bold use of interstitials — an old form that, online, has inspired much (much, MUCH) annoyance — in a way that may make them more palatable to users.

Each article in the WSJ app is branded with an advertiser; at the moment, those include iShares, Capital One, Oracle, Buick, FedEx, and Coke. On the first article page, there’s a small toaster ad in the bottom-left corner, sometimes using “Sponsored by” language reminiscent of NPR. Swipe to the next page of the article and that toaster ad may pop up to show something more like a banner ad. And when you’ve swiped past the end of the article, you get a screen that functions, essentially, as an interstitial: a full-screen display for the advertiser in question. One more swipe gets you past that ad and to the next article, which carries its own branding.

“It’s intrusive but not necessarily interruptive,” says Daniel Bernard, chief product officer for The Wall Street Journal Digital Network. “You can look at it, and if it pulls you in, it pulls you in — and if that one happens not to be for you, you move on to the next one. But you’ve still seen it, and it’s made an impression on you.”

When it comes to the WSJ app’s full-screeners, “we don’t really think of them as interstitials,” Bernard says. The iPad’s UI so changes the calculus of the ad experience that the conventional wisdom about such ads — essentially, to paraphrase legions of web users, that interstitials suck — doesn’t apply as readily to iPad ads. “If you’re online and you’ve got a full-page thing between every article, it might start to feel overwhelming — because you’re online,” Bernard points out. On the iPad, though, it’s different: The swipe has more in common with a print-based page-turn than an online click; what rankles online may fade, and fairly seamlessly so, into the user experience on a touch-based platform.

(In contrast, the New York Times app’s interstitials require you to find and tap a tiny “skip this ad” button to get past the ad without waiting. It’s a small difference from the Journal’s swipe-the-ad-away model, but it feels a lot more like an intrusion.)

In other words: the Journal’s ad-in-app strategy takes a cue from print, mimicking the check-it-out-or-flip-past-it optionality of the newspaper — and, in particular, the magazine — consumer experience. “The best of print doesn’t just mean the editorial judgment of how you lay out all the stories and show their importance,” Bernard told me; “it’s also the ability to have this full-page advertising.” And full-page ads, he notes, are “really impactful, they resonate with users, and advertisers find that they work for getting their message across, as well.”

At the same time, the iPad’s much-vaunted “immersive experience” offers marketers an opportunity to re-imagine that advertising — and, perhaps even more importantly, to encourage consumers to re-imagine their expectations for what that advertising will entail. It’s an obvious point, but one that isn’t repeated enough: Our annoyance — or, for that matter, our satisfaction — when it comes to our consumption of marketing messages is always a function of our expectations for what those messages should be. Marketers and publishers — and, indirectly, editors — have an interest in recalibrating those expectations. The iPad offers one way to do that.

The strategy comes down to leveraging the space between delivery platforms, Bernard says, “to make really great advertising that you can’t necessarily pull off online or you can’t pull of in the paper.” Whether it will prove successful, financially or otherwise, remains to be seen; the hope for the ads, though, at this early stage, is that they’ll fuse “the best of all worlds” — and take the result to the bank.