A new market research survey [PDF] reveals some growing trends, as well as some surprises.  Market research and advertising firm AdMob (which is owned by Google) has combed through millions of advertising requests from mobile devices and surveys and has drawn a wealth of conclusions.

The study takes a snapshot of smartphone users browsing the 15,000 sites in AdMob's network.  

It reveals some intriguing trends in terms of smartphone market leadership.  It reveals that the iPhone has a 50 percent share of the OS market for smartphone devices browsing the internet, while Android is a growing second with about 24 percent market share.  RIM, meanwhile trails with about 4 percent market share.  

Obviously RIM is currently the top smartphone maker when you look at its cross-product sales numbers.  However, iPhone users (and Android users) are using mobile internet much more.  This raises the likelihood both that online content and online advertisements will be aimed more heavily at them, while Blackberry users may see poor compatibility.

The survey also shows India, Indonesia, and the UK to be the closest competitors to the U.S. in terms of an internet-active smart phone user population.  China, curiously, does not make the list.

The study also shows that Mobile Internet Devices (MIDs), like Apple's new iPad, are growing fast in market share.  From February 2009 to February 2010 they grew from about 7 percent to about 17 percent of the total mobile traffic.

AdMob recently conducted a study that showed that 10 percent of smartphone users (approximately) want an iPad.  ComScore, a separate market research firm, recently pegged U.S. smartphone subscription rates at close to 43 million units.  If Apple could indeed sell 4.3+ million iPads, that would be a blow to the device's numerous critics, who include Microsoft co-founder and former CEO Bill Gates.

The iPad launches this Saturday in Wi-Fi form priced at $499, $599, and $699 respectively for 16GB, 32GB, and 64GB models.