Despite the fact that the Palm (NSDQ: PALM) Pre won’t go on sale until June 6, initial users running around in the wild have already started viewing ads on the phone, according to Millennial Media, which released its second-ever monthly mobile advertising report today. While Millennial’s report only represents a portion of the overall mobile ad traffic in the U.S., it’s worth looking at its results given that it is one of the largest mobile ad networks in the U.S. Release.

Besides, the Palm Pre, the company reported that the number of ads served to iPhone and iPod Touch jumped by 8 percent compared to the prior month, helping Apple (NSDQ: AAPL) edge out LG (SEO: 066570) as the No. 2 device manufacturer. At that level of ad impressions, Millennial said the iPhone/Touch set an all-time record for company when it comes to most ads served to a single device during a given month. For the second month in a row, Samsung’s plethora of devices continued to hold on to the No. 1 spot when it comes to the number of ads served to a given handset manufacturer.

Other findings:

—The BlackBerry Storm entered the company’s top 20 list at No. 15.
—Qwerty keyboards surpassed the traditional keypad as the top input method.
—The number of Millennial customers interested in targeting very specific audiences vs. certain demographics grew by four times. That means, rather than targeting users based on simple “meta data,” like gender, a very specific audience was crafted based on information collected on an opt-in basis (for instance, a person’s preferred movie genre).

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