With the iPad officially in the hands of consumers, mobile ad networks and platforms are rushing to create iPad specific ad formats. Medialets, Mobclix, and Greystripe have all created ad formats for the device. And AdMob is said to be releasing its iPad-specific SDK in the next few weeks. Mobile ad network Millennial Media is releasing an iPad-specific SDK and a customized PadMedia Creative Suite that includes new creative ad formats built specifically for the iPad.

Millennial Media’s iPad SDK is code complete, and will be deployed after testing with beta publishers on-device is finalized this week. Developers will be able to download the SDK through Millennial’s developer portal. For advertisers, Millennial Media is releasing its PadMedia Creative Suite, which includes standard mobile ad units and new unique ad formats for the iPad.

These include floating canvas, where a rich media ad will expand upon click, attempting to leverage the canvas of the iPad; RTP (Return-to-Play), which is an ad unit that allows consumers to respond to an ad, pausing their application experience and resuming when they are ready; Motion Creative, which allows ad units to become interactive when the user turns or rotates the iPad in different ways; and full-page Interstitials, which are full-page ads that appear upon application launch or during transition in game play.

Millennial is now one of the largest mobile ad networks in and U.S. According to Nielsen, Millennial Media reaches 83 percent of 72 million mobile web users, across every mobile platform. And the Baltimore-based startup is growing; in February Millennial Media acquired mobile metrics and analytics firm TapMetrics. Additionally, the ad network raised $16 million in Series C funding last November.

Of course, like many of its fellow ad networks, Millennial finds itself in a perplexing situation in the space. It’s unclear how Google’s acquisition of AdMob (although this may be derailed) and Apple’s acquisition of Quattro Wireless will effect the other ad networks in the space. And Apple is announcing its mobile ad plans tomorrow. If anything, these networks will now have to compete with two of the largest companies in the world.

But Millennial Media is wise to being offering innovative ad formats for the iPad and should be able to stand on its own if these formats ends of producing high click through rates.