If you have used the Exchange Server 2013 certificate request wizard in the Exchange Admin Center to provision an SSL certificate, you may find that the Organization Name (O) and Department Name (OU) are displayed incorrectly on the certificate.
However if the certificate request is created using the New-ExchangeCertificate PowerShell cmdlet the resulting certificate has the values listed correctly.
This is a bug that is expected to be fixed in a future update. In the meantime, for correct CSR generation I recommend using PowerShell.
Thanks to forums member PrestonCole who first brought this to my attention.