I have some news about the Notifiy robot (wave-email-notifications@googlewave.com). It can now send notifications to your iPhone when a wave is updated. The application will be available at the App Store very soon.

I just created a google wave robot that sends email notifications when a wave is updated. To try it out just add: wave-email-notifications@appspot.com to the wave and that’s it. It’s currently in a beta stage so there are no guarantees. Visit the project home page at:
http://wave-email-notifications.googlecode.com/