[ZombieBerry]

I am not sure if this applies to an OS 6 device, but RIM changed it somewhere around 7.x.x.xxx so that you can still continue to receive BBMs, etc while your 'Data Services' are turned off. Also make sure that 'While Roaming is set to 'OFF'. Using available WiFi networks or hotspots to access certain BIS services.

Please check with your carrier as Medic mentioned above, as I am not sure if that applies to all carriers or plans. You can always test it right now, by turning Data Services to Off and connecting to your home/school/work WiFi and sending a test BBM and mail to someone.

Cheers,