Today, Motorola announced that the stable version of the Lollipop upgrade for the Moto G 2nd Gen (in the U.S.) and the Moto G 1st and 2nd gen (in India) will begin rolling out. Not everyone will get it at the same time, though, as the update will be delivered in phases.
Moto G owners living in the U.S. and India should be receiving a notification with the update, or they can check for it themselves in the phone's Settings. (Settings > About Phone > System update.)
Motorola did some "soak tests" for its Moto G devices late last year, weeks after Google made the Lollipop version public. The tests were meant to ensure a smoother update process for all Moto G customers once the final version would roll out. It was completely voluntary for those who wanted to get a taste of the new Android version a little earlier, because these soak test versions may have also had some bugs in them. Whatever bugs Motorola found must have been fixed by now if the company is ready to push a stable version out.
Even though Motorola seems to have the Lollipop upgrade ready for the first generation Moto G, which is now being rolled out in India, it seems American Moto G owners are left waiting. This may be a typical U.S. carrier problem. The U.S. carriers often make the phone update process longer than it needs to be because they don't let phone makers upgrade devices without their approval.
The good news is that if Motorola has started rolling out the update for its Moto G devices, then it won't be long until its customers from more countries will get it as well.