Here’s an example of using the very-much beta (maybe alpha) Wavr plugin for Wordpress.
It’s available for use on any wpmu site.
To see it the user needs to be logged in to wave though.
Found it via mashable.com
http://mashable.com/2009/09/08/google-wave-wordpress-plugin/
Plugin page: http://wordpress.org/extend/plugins/wavr/
The hardest part is getting the ‘waveid’.
If you are in wpmu and want to get the ability to edit this wave, leave a comment with your google wave account name, or contact me via email or the wpmu mailing list.