At Google I/O this past May, the announcement that caused everyone's jaws to simultaneously drop to the floor was the unveiling of Google Duplex — a new system that uses the Google Assistant to call businesses and book reservations/appointments on your behalf. Starting today, Google's confirmed that Duplex is now available to use for people in a handful of U.S. cities.

If you have a Pixel phone and live in NYC, San Francisco, Atlanta, or Phoenix, you should be able to start using Duplex either now or very soon. Google confirmed this news to VentureBeat, and as exciting as that is, there are a few caveats to keep in mind.

For starters, Duplex can only be used right now for making restaurant reservations. Google previously demoed the system booking an appointment at a hair salon, but that functionality's not ready quite yet. Furthermore, it's currently limited to just Pixel phones and doesn't work on other Assistant devices like smart speakers or Smart Displays. It's also only available in English right now.

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You can check out the video above to see how Duplex works in person, and as you can see, the process is pretty straightforward. The conversation feels like any other interaction with the Google Assistant, and while VentureBeat does note that it had some issues with certain restaurants not being compatible, that's either due to initial bugs or businesses having the ability to opt out of calls from their Google My Business page.

Commenting on Duplex's rollout, a Google spokesperson said:

We're currently ramping up the ability to book restaurant reservations through the Google Assistant over the phone using Duplex technology. To help deliver a good experience to Pixel users and to businesses, we're starting with a slow rollout … and will expand to more Pixel users as we continue to ramp up.

If you live in one of the above cities and own a Pixel, have you had a chance to test out Duplex yet? Let us know in the comments below!