• by Mark Walsh  @markfwal, April 13, 2010

Apple announced last Thursday that 450,000 iPads had been sold since arriving in stores the prior Saturday. So who are these early adopters? Not surprisingly, they look a lot like iPhone owners. In fact, 43% already have iPhones and nearly half (48.7%) own iPod touch devices, according to a new iPad user survey from iPhone- and iPad-centric mobile ad network AdColony.

Among other findings, the firm found that 44.3% have a household income level of $100,000 or more and 58% have bachelor's or graduate or other professional degrees. More than two-thirds (65.5%) are male, and 34.5% are female.

In terms of age, people 35 to 44 made up the biggest single segment of iPad owners. Those 25 to 34, 45 to 54, and 55 and over each represented about 20% of the iPad user base. The college-age crowd was 7.5%, and teens were just 3.5%. Like iPhone owners, iPad users skew older, male and more affluent than the general population. As more iPads are sold, the typical user may come to reflect a broader cross-section of consumers.

A study by the mobile ad network in January, for instance, found 57% of iPhone users were male, compared to the 65% reported by AdColony for the iPad. The split among different age groups was also more even for the iPhone than the iPad. That more than 4 in 10 iPad buyers to date have incomes over 100,000 is also eye-catching, and seems likely to even out gradually over other income groups.

That's partly because demographic figures for the former are based on a far larger sample, and about 50 million iPhone and 35 million iPod touches have been sold to date.

While the iPad has been described as a big iPod, its minimum $500 price means that most kids will have to rely on a parent buying one to get their hands on the tablet. So the iPad will definitely skew older than the iPod touch audience, which a separate AdMob study last year found was composed 69% of 13- to-24-year-olds.

So when it comes to the audience it represents, at least initially, the iPad is more like a big iPhone. While brands may have to rejigger their ad formats to take advantage of the iPad's larger screen and unique features, they don't have to recalibrate their messages to a much different segment.

AdColony, a unit of mobile developer Jirbo Inc., specializes in serving video ads in iPhone and iPad apps for clients including CBS Mobile, Initiative, Sony Pictures, Lionsgate, and Scion.