1. A method of processing motion events, the method comprising: at a server system having one or more processors and memory, wherein the server system is configured to process motion events for each of a plurality of smart home environments remote from the server system, each smart home environment of the plurality of smart home environments corresponding to a distinct set of one or more cameras, registered users, and client devices: for a first smart home environment of the plurality of smart home environments, wherein the first smart home environment corresponds to a first set of one or more cameras, a first set of one or more registered users, and a first set of one or more client devices: obtaining a video stream from a camera of the first set of cameras, the video stream corresponding to a field of view of the camera; obtaining, on a client device of the first set of client devices, identification of a user-defined spatial zone corresponding to a portion of the field of view of the camera; and for a motion event detected in the video stream subsequent to obtaining the identification of the user-defined spatial zone: determining whether the motion event involves the spatial zone; characterizing motion of the motion event, including analyzing any portion of the motion that occurred within the spatial zone; storing video information of the motion event at the server system, including storing the characterization of the motion and one or more images of the motion event; in accordance with a determination that the motion event involves the spatial zone, suppressing a first user notification for the motion event; and in accordance with a determination that the motion event does not involve the spatial zone: generating a second user notification for the motion event; and sending the second user notification to the first set of registered users via the first set of client devices.