Watch out Skype, because Google is on your heals. Today Google announced that they have integrated into there email service, Gmail, a Voice over IP system, that will allow all it’s users to talk to anyone with a land line phone or cell phone for free within Google’s email service.

The Google Voice VOIP Gmail service is beginning to roll out today for US Gmail accounts. Gradually it will be integrated into all US accounts over the course of the next several days, so if you don’t notice Google Voice in your Gmail account just yet, don’t worry. Here is what we know about the service thus far:

* All calls from within the United States and Canada are free of charge. Calls to other countries will be a flat 2 cents per minute charge.
* You can easily make outgoing calls and receive incoming calls to landlines and cellphones all over North America.
* With Google voice, you can add multiple phone numbers, and have it ring multiple numbers at once when you receive a call. This has been a feature of Google voice for some time now.
* A Previous Google Voice account is not needed if you want to make calls within Gmail.
* The audio quality is supposedly top notch.
* Google already has plans to install phone booths which use Google Voice, so that people can make free calls at airports as well as college campuses across the country.

Thus far, the few people who have access to the service are quite impressed. “Starting today, you can call any phone right from Gmail,” blogged Robin Schriebman, a Google software engineer, “We’ve been testing this feature internally, and have found it to be useful in a lot of situations, ranging from making a quick call to a restaurant to placing a call when you’re in an area with bad reception.”