Google announced today that its Nexus S Google phone, announced last week, is now available in the U.S. starting today. The device can be purchased through Best Buy and Best Buy Mobile stores online and offline. 

"With a brilliant 4" Contour Display, a 1GHz Hummingbird processor, the latest Google mobile apps and Android 2.3 (Gingerbread) pre-installed, we’re excited about getting this great device out there," says Product Marketing Manager Kenzo Fong Hing.

The phone is sold unlocked for $529.99 without a service plan or for $199.99 with a T-Mobile service plan.

The phone’s predecessor, the Nexus One was widely regarded as one of the best Android devices, if not the best. Google launched that with an experimental phone store, in which it sold the phones directly to consumers without contracts, but that didn’t go over so well, and the store eventually closed (though it later resurfaced as a way to browse different Android models from other providers). The Nexus One eventually became available as a developer phone. 

Gingerbread, the latest version of Android is one of the big draws to the Nexus S.

 "We co-developed this product with Samsung—ensuring tight integration of hardware and software to highlight the latest advancements of the Android platform," said VP of Engineering Andy Rubin. "As part of the Nexus brand, Nexus S delivers what we call a ‘pure Google’ experience: unlocked, unfiltered access to the best Google mobile services, and the latest and greatest Android releases and updates."

Upon last week’s announcement of the Nexus S, Rubin said Google would be open sourcing Gingerbread in the coming weeks.