Review: Motorola Moto G for AT&T
The G loses Moto Voice and Moto Connect, but keeps Moto Assist and Moto Migrate. The G doesn't have the X's co-processor so it can't handle Moto Voice. This is part of how Motorola was able to keep the cost down.
Moto Assist
Moto Assist helps users manage notifications to prevent interruptions, such as when sleeping, when driving, and when in meetings. It automatically detects when you're driving, and can be set to enter sleep mode on a set schedule, if you wish. It also knows when you're in meetings. You can also allow select contacts to break through sleep mode. It's a useful tool, but has been replicated by most other smartphones these days.
Migrate
Moto Migrate is meant to help you transfer all of your content from one device to another. It works with media, call and text history, as well as SIM contacts. The tool makes use of a QR code scanner to pair the two devices and then uses Google's servers to migrate the data between the phones. It makes it pretty easy to send data to another device. This functionality now also works with feature phones and can be used to transfer contacts through a Bluetooth connection. That makes the G a bit more appealing for someone switching to their first smartphone.