Partners are asking "how can I estimate how email on Exchange Online will impact bandwidth".
Good question.
Good answers: http://technet.microsoft.com/en-us/library/cc540453.aspx
Also see: http://www.microsoft.com/resources/Technet/en-us/MSOnline/bpos/index.html?page=html%2F3dea7174-a521-4442-a7c5-5d540e09b20d.htm
-brett
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