You PB is a device, it's not a phone.
What if you lose phone what happens do all those contacts?
There are so many what if's. Start using MS Outlook and doing contact sync's with your device so you don't have to worry about someone hacking into your google or hotmail email accounts. Maybe down the road there will be away for you to sync your contacts from your Outlook to your Playbook.
The request your making isn't an enterprise business solution, RIM has always gone in that direction. Then again maybe RIM isn't you and you should look at something less secure like Apple, just a thought.
A.