It appears that the Apple iPhone, one of the hottest gadgets from one of the most cutting-edge companies in the world, may kick mobile advertising up a notch.

According to Brightkite, Inc. and Gfk NOP, iPhone users are more likely to recall mobile ads than non-iPhone users.

iPhone users had higher rates of recall from all measured types of mobile ads than nonusers, including mobile display, standard text message (SMS), audio, picture or video messages (MMS) and mobile TV and video ads.

That’s great news for marketers, particularly at a time when other mobile manufacturers are building more touch-screen smartphones, such as the BlackBerry Storm, Palm Pre and Google Android.

But are iPhone users a viable demographic target? After all, Nielsen estimated that only 5.9% of US households owned or rented an iPhone in Q3 2008.

That number is sure to grow.

The NPD Group data ranked the iPhone as the second-highest-selling smartphone in 2009, and a Skype survey conducted by Zogby International ranked it the second-most-popular smartphone in the country, after the BlackBerry.

Enthusiasm for the device is also high among current users. Based on a customer satisfaction index, J.D. Power and Associates ranked Apple as the No. 1 smartphone brand in the second half of 2008.

According to a survey by Rubicon Consulting, most iPhone users are young (under 30), technologically sophisticated and apt to buy gadgets.