I'd like to get some other BES Admin's opinion on this one. Part of me thinks that this will solve some problems, while another part of me thinks that this will eliminate some BES Admin positions.

Office 365 and BlackBerry - Microsoft Office 365 Blog - Office 365 - Microsoft Office 365 Community

I llike an inhouse system that I control.

I think it has the pro and cons of all the solutions you move to the cloud. Many companies fear that they lose control over their data if it is somewhere in the cloud.

Biggest issue with cloud/hosted is that you are not able to control much. many hosted BES solutions will not allow you to change much of anything and you end up with reconcile issues, prepopulation issues, hard deletes not enabled and more.

just search hosted BES and you will see many pains others have gone through.

We got the opportunity to check this earlier this year, so my 2 cents from attending presentations, but I may have incorrect info.. No, we didn't go with Office365.

The mail is hosted by Microsoft, BIS is hosted by RIM (No, this is not BES). The admin control is limited to basic items like adding/removing users, set activation password etc. Don't expect BES policies or the control or any troubleshooting from your company. Do check who supports user if BB fails as we couldn't get that answered.