Far more iPhone owners are “very satisfied” than owners of other smart phones, according to data from a ChangeWave Research survey conducted March 17-24.

Furthermore, the iPhone’s market share increased 50 percent, from 6 to 9 percent, since a January survey.

ChangeWave, a Rockville, Md.-based research company, conducts periodic surveys from amongst the members of its “ChangeWave Alliance” on technology and business trends.

The results of this survey, focused on consumers, echoes the results from a similar ChangeWave survey on corporate smart phone purchasing taken in February. (See my blog entry on that here.)

The customer satisfaction chart shows Apple leading with a breathtaking 79 percent of owners saying they are “very satisfied,” handily beating Research in Motion’s (BlackBerry) 54 percent.

The market share numbers show Apple gaining, but mostly at the expense of Palm, which has declined from 23 percent when the iPhone went on sale in July of last year to 16 percent in the March survey.

Somewhat ominously for Apple, RIM’s market share has increased since the iPhone’s launch, from 38 percent last July to 42 percent in the most recent survey. Perhaps as Apple builds upon the iPhone's potential as a WiFi mobile platform, it will begin to eat into the BlackBerry's market share.

Nevertheless, Apple managed to pull into third place in the smart phone market in just nine months, disproving the negative predictions of the iPhone’s doubters last year.

Of those respondents who plan to buy a smart phone in the next 90 days, Apple scored its highest number yet – 35 percent plan to buy an iPhone, compared to 29 percent planning to buy a BlackBerry. That’s reversed from January, when 32 percent said they expected to buy a BlackBerry versus 23 percent for the iPhone.

ChangeWave attributes this dramatic shift partly to Apple’s announcement in January of the availability of the iPhone software development kit, which promises to greatly expand the iPhone’s capabilities relative to its competitors.

However, when asked this directly, only 10 percent of the respondents said the iPhone SDK announcement along with the iPhone road map and Enterprise beta program made them “more likely” to buy an iPhone in the future, with 79 percent saying none of that mattered.

One other noteworthy portion of the survey concerns cellular providers. In the chart showing future buying plans by provider, the iPhone appears to have had a dramatic impact on AT&T’s business.

Through 2006 AT&T’s numbers hovered in the mid-teens. But in January 2007 – when Steve Jobs announced Apple’s partnership with AT&T as the exclusive carrier for the iPhone in the United States – AT&T’s number jumped 43 percent. In the April survey, AT&T overtook Verizon, and has remained ahead in each survey since.

The number of people saying they planned to switch to AT&T hit a high of 30 percent in July 2007 – when the iPhone went on sale. In the current survey, AT&T holds a 6 percent lead over Verizon.

The draw of the iPhone could have provided an even bigger pop to AT&T’s numbers save for one problem – its customer satisfaction numbers seriously lag Verizon’s. Only 28 percent said they were “very satisfied” with AT&T compared with 42 percent for Verizon.

Looking at it another way, one wonders how many iPhones Apple could have sold had it been possible to sign Verizon as its exclusive partner.