Google started sending ‘email notifications’ about new and updated waves in your inbox! To test it out, just use the dropdown menu by the Inbox link. “From Notifications menu, you can select frequency of your email updates. If you’re an infrequent Google Wave user we would recommend the "immediately" setting, but you can change it at any time. When you're added to a new wave, or a wave that you’re on changes, we'll send you an email with a short summary of the text and links to go straight to your updated waves. Rest assured, we know waves can change a lot, so we will only send you one notification about a changed wave until you have logged in to look at it (i.e.: if a wave changes 10 times after we send the first notification, we won't send 10 more emails). Waves you have open also won't trigger updates,” noted Google.