Google Wave has just updated itself with two brand new spankin' features: the ability to add participants who can only read a wave, and the ability for any participant with full access to a wave to restore the wave to any previous state visible in playback.
Read Only Participants
As the
creator of a wave, I have the ability to add and make participants in the conversation to either have
full access to the wave or
read only access. In the wave that you have created, click the picture of any of the participants at the top of the wave, and you'll see you have an option to change their permissions.
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