Update 1: Google has in fact unveiled the new Nexus One phone, and it is now available for purchase. The Nexus One product page is now also live on the Google website. Head over to Engadget who is blogging live from the Google press conference.

Google has announced an Android press event on January 5 at its Mountain View, CA headquarters, where the company will unveil the first mobile phone it would be selling to consumers directly, the Google Nexus One phone.

The phone will be offered through T-Mobile and will be priced at $530 unlocked, or for $180 with a two-year term that requires customers to add voice, text, and a data plan for a minimum of $79.99 per month.

The Nexus One will be powered by Android 2.1 with a 1GHz processor, and will include a 3.7-inch display (480x800px resolution), 512MB of ROM and 512MB of RAM, GPS, an accelerometer, a 5MP camera with LED flash, among other features.

As publications such as AOL’s Engadget tech blog have already been provided a Nexus One and have published a brief walkthrough of the device, it is clear that Google will use the January 5th event to officially unveil the device.

To date, Google has been pushing its open-source Android OS to phone-makers such as Motorola and HTC (HTC is the manufacturer of the Nexus One, the same company that makes about 85-percent of all Windows Mobile powered devices), who have respectively launched their own Android powered devices, most recently the “Droid” phone from Motorola. The first Android powered device launched in October of 2008.

Other phone-makers confirmed they would launch their own Android powered handsets in 2010, however, the Nexus One represents the first Android powered handset that will be sold to consumers directly from Google.

As more people access the web from their mobile devices, Google must solidify its dominant web advertising position in the mobile realm. Providing phone-makers with the option of powering their handsets with the open-source and highly advanced Android operating system, and now by selling the Nexus One directly to consumers (who can use the phone on any carrier), will only help ensure Google remains the king of web advertising.

Google most recently acquired AdMob, a mobile advertising network, for $750 million.