As is its custom, Google has for several years been quietly -- some might even say secretively -- building up the infrastructure to support its apparently vast mobile plans. Since the start of the millennium, Google has been purchasing dark fiber (also known as unlit optical fiber), laid in preparation for the internet boom but as-of-yet unused by the telcos. Earlier this year, iMedia wrote about the potential for Google to light its dark fiber and lower transmission costs, especially to Asia.

In addition to dark fiber, Google announced in July that it intends to bid in a January 2008 auction for licenses for the 700 MHz electromagnetic spectrum controlled by the Federal Communications Commission. Broadcasters now use that spectrum for television, but it's likely Google will want to use it for broadband communications to establish an open wireless broadband network. The Mountain View, Calif.-based search giant may also bid on the 900 and 1800 MHz spectrum in the U.K.

In case you were thinking Google may have started to relax a bit after a busy summer, well, September was another busy month for the company. That's when Google announced it had extended its AdSense contextual text and image advertising program to mobile. The mobile version of AdSense is designed for users who have optimized versions of their websites for easy navigation on wireless devices. (That's only 8 percent of the websites for the top 1,000 U.S. brands, according to an eMarketer study.) Mobile AdSense is now available in the U.S., England, Italy, France, Germany, Spain, Ireland, Russia, Netherlands, Australia, India, China and Japan.

Later in September, Google revealed it had acquired Boston-based startup Zingku. Still in private beta, Zingku lets users share content among themselves and between the desktop and mobile devices. The company also has a program for merchants interested in distributing mobile-specific flyers to announce new products or upcoming events.

And just last month, in a display of appreciation for consonance following the Zingku purchase, Google announced the acquisition of Jaiku, a Finnish Twitter wannabe. Jaiku is a free service that lets users follow their friends' activities in real time.

There's also the Gphone, long-rumored to emerge as an iPhone competitor. Recent reports from PC World and The New York Times, however, suggest that the Gphone won't be an actual device but rather an open source mobile operating system set to challenge Microsoft's dominance in the mobile space with its Windows Mobile operating system. If the new crop of rumors proves correct, Google might just shake up the entire mobile market by softening the longstanding grip on the industry by the wireless carriers.
 
As has become custom, it seems that with both its infrastructural developments and its incremental software acquisitions, Google has positioned itself for mobile dominance.