Indeed, that feature is Siri, and in the ad, Jack is in an unnamed carrier's retail store. He tries out what doesn't looks to be a iPhone 4S, but come on: we know it is supposed to be.
The "conversation" goes as follows:
Salesman - "Go ahead, try it."
Jack - "Where's the nearest Jack in the Box?"
Siri - "I found four places that sell socks."
Jack - "Not socks. Jack in the Box."
Siri - "A yak is a long-haired bovine."
Salesman - "That's true."
Jack - "I like things that work. Like my no-nonsense All America Jack combo (describes it further)."
Salesman - "Sounds delish."
Siri - "I found one D-list celebrity nearby."
Siri was the big differentiator between the iPhone 4 and the iPhone 4S. Despite Apple's heavy ad campaign, there are quite a few people who feel the feature is still not up to two. Apple is even facing lawsuits in the matter.