Google Voice is moving forward. Whereas the application was just available to users of GrandCentral (a service Google acquired in mid-2007), all of the people who have requested access should now (or at some point in the near future) be receiving invitation emails.
Google Extending More PPA Invitations
AdWords clients may see an invitation to join the beta test of Google’s pay per action (PPA) advertising appear in their accounts.
Yahoo’s Latest Move: Upgraded Sponsored Search Invitations
Yahoo’s upgraded Sponsored Search invitations: Features, benefits, challenges, and the potential future of search advertising with Yahoo.