Wall Street Journal is reporting that Apple has lost the #2 market position in mobile ad sales to Millennial Media – the largest independent and now #2 in mobile ad sales. Bloomberg is also reporting the story.

Last year according to IDC data, Apple shared the top spot in the mobile display ad market with Google, with each company capturing 19%. This year, Apple fell to the No. 3 spot, behind Google and independent mobile ad firm Millennial Media, capturing 15%, or $95 million, of the $630 million market, IDC says.

Google’s share of the market for 2011 will rise to 24 percent share, from 19 percent in 2010, said IDC, a unit of Boston-based International Data Group. Millennial’s share will climb to 17 percent from 15 percent, as Apple’s declines to 15 percent from 19 percent, IDC said today.

The three companies are the largest pursuing the U.S. mobile advertising market, which will more than double to $2.1 billion this year, from $877 million in 2010, IDC said. Google has solidified its market lead, and Millennial has assumed the No. 2 position in mobile ads.

“This is primarily a story about Apple’s weakness,” Karsten Weide, a program vice president at IDC, said in an interview. Many advertisers opted for competitors’ ad networks, so they can reach both Apple and non-Apple devices, he said.

I’ve been covering Millennial Media going back to when they just were getting started. CEO and industry veteran Paul Palmieri has really done an amazing job leading Millennial Media to not only become the #1 independent mobile ad firm but overtaking Apple is a real accomplishment.

Millennial Media continues to innovate with their SMART report the definitive guide to the top mobile trends. Here are some highlights from Millennial Media October SMART report

October SMART report

Entertainment Spotlight

· Motion Picture releases were the top subcategory in the entertainment vertical, making up 42 percent of all campaigns. TV and DVD releases were in the second and third spots, respectively.

· Promoting a product launch/release was the top goal for entertainment advertisers, making up 50 percent of all campaigns. Advertisers most frequently promoted releases of new movies, TV shows, and DVDs.

· Over 50 percent of entertainment campaigns gave consumers the opportunity to watch a video. This was more than double the overall average for all verticals.

· 23 percent of entertainment campaigns included mCommerce as an option (again, more than double the overall average). This was used to allow consumers to purchase movie tickets, DVDs, etc., directly from their devices.

October SMART Highlights

· Campaigns that directed consumers to an app download page (as opposed to a website or landing page) increased 33 percent month-over-month and made up 29 percent of the total campaigns on our platform.

· Campaigns with a “Store Locator” grew 5 percent month-over-month and made up 23 percent of our total campaigns. Retail advertisers in particular used this to help drive store traffic.

· Sustained In-Market Presence remained the top campaign goal on our platform and represented 37 percent of all campaigns.