Google is telling IT executives to hold on, perhaps until later this year, as it prepares for for the rigors of business.
The invitation process had been shut down late last week because of 'insane demand' from people eager to try out Google's new social network.
After the Google-Twitter partnership expires, Google suspends its Realtime Search service.
Analysts say it won't be easy for Google+, the new social network from Google, to lure users away from Facebook, the world's largest social network.
Stone will leave his day-to-day duties at Twitter to focus on non-profit ideas and new projects.
Articles by Sharon Gaudin