[originl]

I think it also depends on what sort of business activities you usually connect to.

Do you connect to an intranet SharePoint or other websites over WiFi/VPN?
What sort of security does your IT have in place to limit or authenticate users, etc.

I've found that Blackberries, while easier out of the box to connect to and access Corporate information, can also be done with a Windows Mobile device with the know-how. Then again, this is all up to your IT department's setup and restrictions. I'd ask your coworkers with the various devices.