Google announced Chrome OS in a blog posting Tuesday evening, saying it would be available for consumers in the second half of 2010 initially aimed at netbooks using x86 or ARM processors.

The company declined to provide interviews or answer questions on the hardware requirements and software components of the OS. "We are still coding and in early conversations with OEMs and others, so these technical decisions have not been made yet," said a Google spokesperson.

The announcement ends months of speculation Google might create for netbooks a variant of its smart phone Android OS. Instead it opted to create a lightweight OS under its Chrome browser released in September, it claims is now being used by 30 million people.

An early version of that OS has already booted on Freescale's i.Mx515 integrated processor designed for netbooks. The chip uses a GHz-class ARM Cortex A8 and 512 Mbytes DDR2 memory.

"Our customers are interested in a significant brand and backer for an alternative software strategy and Google has the muscle to do this," said Glen Burchers, a consumer marketing director for Freescale. "Several of our largest customers are intrigued," he added.

Freescale first heard about the effort "sometime between February and now," said Burchers. He heard about it from "one of our mutual customers, a large customer, who was previously focused on Android for netbooks, but they have now shifted to Chrome," he added.

The news will push out by as much as a year the launch of some Linux/ARM netbook designs originally planned for late this year. Other OEMs will roll out this year ARM/Linux netbooks using Ubuntu's distribution of Linux.

"Our first customers are coming out with Ubuntu systems," said Burchers."There may be some people that still do Android netbooks, and we still have a board support package for it," he said.

However, Android is focused on the smart phone. Even its next generation will only natively support up to 854 x480 pixel resolutions.

Long term the Android/Chrome OS split probably makes sense for Google, keeping separate teams focused on smart phones and larger computer-like devices. By rolling out a separate code base for netbooks, notebooks and desktops, Google reduces the risk its Android effort will become fragmented, something that has happened to other mobile Linux variants.