MLB.tv has two full-season pricing options: $119.95 for the season/$24.99 a month for access to MLB.TV Premium and $99.95 a year/$19.99 a month for the basic video package. Each level included full portable access to that “.tv” subscription across a range of mobile phones within the At Bat apps as well as other connected devices (PS3, Roku, Boxee, among others). The At Bat apps are $14.99 for each of the various platforms (iPhone, iPad, BlackBerry, Android). Other devices that can handle the live streaming will be added as they hit the marketplace (Xoom is one likely candidate) over the course of this season.

Volvo’s involvement with MLB.com is part of the automaker’s larger digital ad strategy for 2011 and is focused heavily on sports this spring. It’s also sponsoring he Big East basketball conference. The strategy has been crafted with Mobext, the mobile marketing agency for MPG/Media Contacts, Volvo’s media buying shop. Volvo’s campaign for the MLB.com will also run on the league’s Facebook FanPage and through Twitter. This “opening day” sponsorship is only available across Apple’s iPhone, iPad and iPod touch.

The month-long free trial underscores the increasing importance of mobile video to MLBAM’s efforts. The company expects mobile usage to outpace wired in a year or two. That’s the reason its carefully trying to build its own ad system this season.

The surge in mobile activity is impressive. For example, three years ago, mobile comprised 8 percent of MLBAM’s traffic; in 2010, it represented 37 percent of all of MLBAM’s vistors. On the video front, in 2010, MLBAM, the digital business arm of Major League Baseball, said its viewers racked up 9.5 billion minutes of streaming ballgames across all devices.