Most Popular BlackBerry Download? MySpace.

BlackBerry users have a reputation has being boring government and enterprise types who like to use their technology to “capture details,” “enable collaboration,” “optimize operational granularity”…and, of course, grumble about using Microsoft Exchange. But it turns out many BlackBerry users have a social side, as well: Research In Motion has announced that its MySpace for BlackBerry application was downloaded more than 400,000 times during its first week of availability, which is a new all-time high for application download for both MySpace and RIM.

“This rapid adoption is a reflection of an evolving consumer lifestyle where social connectivity and information access are more important than ever,” said RIM co-CEO Jim Balsillie, in a statement. “This powerful new mobile application combines social networking and mobility in a highly personalized and empowering manner and we are very excited to see such a positive response in the first week.”

RIM likes to describe the application in very enterprise-y terms—”optimized to deliver rich content”, “integrates MySpace’s primary social networking components,” “instant, push-based messaging” blah, blah, blah—but what it really means is that user can whip out their BlackBerriesys at lunch (or over a dirty martini, or something) and say “See? I told you like 300 people had friended me!” The application also reflect’s RIM’s growing emphasis on the consumer segment of the smartphone market, as mobile users come to expect greater capabilities from their mobile devices.

The MySpace for BlackBerry is available for the BlackBerry Bold, Curve, Pearl, and 8800 series—and, as of yesterday, for the BlackBerry Storm.