Apple isn't particularly known for using celebrity endorsements in its marketing campaigns, with TV commercials tending to put the product front and center. With the iPhone 4S, however, the main differentiator is Siri, a feature that requires the human voice — and what better humans to use than Samuel L. Jackson and Zooey Deschanel? Both have appeared in separate commercials starting to pop up across TV networks, which feature the actors holding natural and productive conversations with their iPhones and discussing everything from the weather to measurement conversions. Oddly, the spots promote separate carriers, with a Verizon logo appearing at the end of Jackson's and Deschanel's giving the nod to Sprint — we wouldn't be shocked to see another celebrity commercial pop up under AT&T's banner. That is, assuming the carrier hasn't exhausted its marketing budget on the Lumia 900.

Update: we've swapped out the videos with direct feed versions, and the Samuel L. Jackson video indeed carries AT&T's logo this time. It doesn't seem like there's any rhyme or reason to the individual branding, but at least we know all the iPhone carriers are being let in on the fun.