More than 1 million calls were placed from Gmail's free calling service in its first 24 hours, according to Google, which launched the service Wednesday. When we tried it out, we found that Gmail calling has remarkable ease of use, making it almost phone-like, despite originating from an e-mail program. This is a relief considering Google's confusing and vilified Google Buzz social newsfeed also originated within Gmail. Still, at the get-go, there are some problems.

My colleague Wilson and I had a 12-minute conversation using the "call phone" feature. He called my cell phone from his Mac, and his voice was remarkably clear. That's all the more impressive considering he had to talk through the computer's built-in microphone, which always tends to make people sound like they're in a big, empty basement.

Setting up the service was "a snap," he said, taking all of 30 seconds. All that was needed was a browser plug-in installation and a quick browser restart. Wilson used Google's Chrome browser.

When he called, my phone showed that he was calling from 760-705-8888. This is the number everyone will see when receiving calls from Gmail callers. It's no good for calling people back — if you call the number, you hear a promo for Gmail. If the user is logged in to Google Voice, however, the Gmail calling will display that person's Google Voice number, which may very well match up to the number you have for them in your contacts. Of course this number can be used to get back to the person.

However, my attempts to set up the service on two computers — Firefox on my Mac, IE on my PC — were not successful. Despite downloading the needed free voice and video chat software, the "call phone" link did not show up in my Gmail chat list on the left side of the screen. There are some others out there having similar problems, sharing that complaint in Google's support forums.

"We're slowly enabling this (call phone) feature in Gmail accounts ... through the next couple of days," Cody W., a Google support rep, said on the site. "This is separate from installing the voice and video chat plug-in. If you do not see the 'Call phone' link in your Gmail chat list and your interface language setting is 'English (US)' (found via the Gmail settings link), it is most likely because that particular Gmail account has not been enabled yet. Installing the voice and video chat plug-in will make you ready for when it is, regardless of account."

Another problem some users are having is getting an error messaging saying their call cannot be completed. "This is a known issue that we’re actively working on fixing," Cody wrote. "While it should not require a full featured Google Voice account to make outbound calls in Gmail, a temporary workaround if you receive this error is to upgrade your Google Voice account to a full account." Instructions on how to do so are here.

For now, the program lets users of Google's free e-mail service make free calls within United States and Canada. I say "for now" because Google says clearly that free is not forever, but will be so for "at least the rest of the year."

"Calls to other countries will be billed at our very low rates," starting at 2 cents per minute, the search giant says on its blog. "We worked hard to make these rates really cheap (see comparison table) with calls to the U.K., France, Germany, China, Japan — and many more countries ..."

With more than 150 million users, Gmail is third behind Microsoft and Yahoo as the most popular free e-mail providers in the world. Analysts think the Gmail service will be a threat to Skype, which already offers free computer-to-computer voice and video calling. "It's a competitor with a pretty good brand name," said Hudson Square analyst Todd Rethemeier.

Facebook, with more than 500 million users worldwide, seems like the next likely candidate to jump in the calling game. The social networking site, free to use, has more than 500 million members, and a plethora of users' phone numbers posted on personal profiles and throughout the site. A growing number of Facebook users send e-mails to each other from within the site's confines, and it already has a Web-based instant messaging service enabling friend-to-friend chat. Why wouldn't voice chat, and real phone calling, be next?

As I mentioned, using Google Voice with the Gmail "call phone" feature enhances its experience, even though a Google Voice account is not a prerequisite. Many people still don't know what to make of the service. It was rolled out in the spring of 2009 to a limited number of users, and became widely available almost a year ago, and is now used by 1.4 million people.

Still, it's hard to say whether Gmail's new calling service will help swell the ranks of Google Voice users, or will just give people even more reason to ignore it. It may prove to be a case of Google beating Google at its own game.