Google Launches Multiple Account Sign-In for Multi-Google Account Holders

• You can sign into a maximum of three accounts at once.
• The first account you sign in with when you're setting up multiple sign-in will be set to your default account
• You can't use Offline Gmail or Calendar with the multiple sign-in feature.
• Multiple sign-ins only work with these Google apps—that is, Google App Engine, Code, Calendar, Gmail, Reader, Sites, and Voice support the multiple sign-in feature. Most notably, Google Docs isn't yet supported, but it's marked as coming soon.
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