My (smaller) company has an existing Google Apps Deployment, used for E-Mail / Calendar, etc.

I'm looking into a SharePoint setup (2010 most likely). One of the best features is that new events are added to one's Outlook Calendar, e-mails can be sent automatically, etc. Naturally, this works best out-of-the-box with Exchange.

I know I can add my own OpenID login system via an OpenID provider for SharePoint and get my users into the system.

My question is, can anyone recommend the best way to go about making sure that events automatically find their way into users' calendars and e-mails on the Google Apps system?

This would enable us to deploy SharePoint without worrying about migrating our e-mail system to Exchange first (Google Apps is more cost-effective for our needs and I'm required to keep it.)

Thanks in advance for any help!