The following is the details about Google Wave, Google’s very ambitious (open source?)effort to takehold of the social networking movement– it is derived from the fairly ample information (but no accessible demos except by permisso) on the Google Wave API pages plus a Business Week overview. Here is the schematic: 
The key idea with Google Wave is to create conversations among partys in a Web context. See BuddyPress.org for another and definitely Open Source take on the idea. Also think of Google Wave as texting carried to the nth power. The current and next wave of Smartphones and Netbooks will be perfect vehicles for Google Wave Apps. Expect the mobile carriers to be developing(and encouraging the development of) Wave apps. The technology is squarely Web 2. Developers use JavaScript to do the presentation for parts of the Google Wave Embed API being placed into a website or blog. In addition there is a Extension API codable in Java or Python to allow developers to create more sophisticated widgets for use within the Wave framework. With JavaScript on can generate some very good embedded widgets startaight away. In the half dozen sample Wave embeds shown – jQuery JavaScript framework was the only major JavaScript framework I could see.
Go here for the Google Wave API details(expect changes according to Google).
Go here for analysis of Google wave versus RIA – not convinced its an RIA killer
Go here for the PR triumph of Google Wave as it tsunami-ed Bing
But I am convinced it will eat into Facebook, BuddyPress.org, WordPress/Drupal/Joomla and the other Blogs.
personally i like google wave quite a lot