Wave is a difficult service to "just jump into" (or so I find it). Here, therefore, are a set of resources that might prove helpful to others:
The Complete Wave Guide: http://completewaveguide.com/
5 ways to use for business: http://mashable.com/2010/03/08/google-wave-business-uses/
5 ways to use for business: http://mashable.com/
Google Wave Guide: http://mashable.com/2009/05/28/google-wave-guide/
Wave for Business: http://mashable.com/2009/12/18/google-wave-business/
4 uses for Wave: http://mashable.com/2009/12/15/surprising-google-wave-uses/
Wave and the News: http://mashable.com/2009/11/22/news-media-google-wave/
I'd certainly welcome additional useful references!