Apple (Nasdaq: AAPL) just can't seem to lay off hiring celebrities for its whimsical iPhone ads that promote the smartphone's voice-activated digital assistant.

Iconic movie director Martin Scorsese is the latest star in a series that has treated viewers to Samuel L. Jackson making mushroom risotto, Zooey Deschanel getting giddy about the weather, and John Malkovich hankering for some Portuguese sausage.

Placing stars in everyday situations may have seemed like a good idea at first, but things are different now that the viability of Siri itself is coming under fire. Some tech reporters are arguing that Google's (Nasdaq: GOOG) new Google Voice Search for Android devices is superior, and even Research In Motion (Nasdaq: RIMM) is working on a voice-recognition platform for its upcoming BlackBerry mobile operating-system update.

However, the Scorsese ad does raise the bar. In the 30-second TV commercial, Scorsese is in a cab -- driven by someone with a hint of Taxi Driver's Robert De Niro -- as he uses Siri to move appointments around, navigate his way through traffic, and even use the iPhone's Find My Friends feature.

It's still whimsical, but at least it plays up the utility of the device.

Does the ad touch on the complaints that Siri has a less-than-stellar track record of recognizing requests and responding correctly when it does understand the command? Of course not. This is marketing. It's the glamorized serving suggestion on a microwave entree box.

Apple had just better hope that it's not merely educating the marketplace for something that Google or an even hungrier competitor may somehow do better later this year.

After all, way too many of my Siri requests seem to be met with De Niro-style "you talking to me?" replies.  

Apple jacks
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