@Ian Ray:  While second factor authentication is not for everyone, organizations adopting it have a need for this level of user security and consider both human factors and costs in relation to benefit. I offer no guidance regarding sustainability of other, potential 2nd factor authentication methods to Office 365, as we look to partners and customers for feedback on these potential methods, based on their experience using them with the cloud service.

@Ian Ray: Those wishing to implement RSA SecurID for two factor authentication might begin by reviewing this blog post. It describes using federated identities in Active Directory with Office 365. (http://bit.ly/xvW2eS). We look forward to hearing about customers’ and partners’ experience with other 2 factor methods in authenticating to Office 365!