So soon after Google promised Atlanta, Georgia, gigabit broadband, Comcast has said it will offer 2Gbps internet to homes in the city in May – and millions more Americans by 2016.

The US cable colossus announced Thursday that its 2Gb/s Gigabit Pro service will debut in Atlanta, reaching 18 million homes across the US by the end of the year, potentially.

Comcast said Gigabit Pro will be available first to Americans living near its fiber broadband network. Those who are "within close proximity" to the Comcast backbone will be able to get a fiber line directly to their home.

Comcast did not admit what the Gigabit Pro service will cost per month, and what installation fees users may incur for having a fiber line installed.

The advertised 2Gbps speeds would be double that offered by Google's Fiber service in Atlanta. The Mountain View ad-slinger listed Atlanta among a handful of cities where it plans to launch Fiber in the coming months.

Where Fiber has been launched, high-speed services from other telcos have followed. In markets such as Kansas City, MO and Austin, TX, competitors like Comcast and AT&T have found ways to launch their own home gigabit offerings to compete with the Chocolate Factory.

Earlier this week, AT&T announced plans to expand its GigaPower internet service to Silicon Valley with a limited launch in Cupertino. That service will be one of the few home gigabit plans to be offered in a market Google has yet to reach, though it comes with a hefty surcharge and privacy hangover. ®