Now, when Google+ for Google Apps is available, the most prominent feature missing is the Google+ Hangout and Google Calendar integration.
Today, Hangouts are ad-hoc process, i.e. you start the hangout and wait until people are get connected. You can not schedule Hangouts to start at particular time/date. Unfortunately, this is not how we use video-conferencing systems, usually.
It would be great of Google will provide the way to schedule Hangouts as simple Calendar meeting request and to provide some sort of "Join Now" button in the event itself when the Hangout is available to join it.
What do you think?