We've had voice services built into BlackBerry 10 since day one, although they are quite limited in comparison to the likes of other mobile platforms. In fact, using voice services when I'm in the car is something I very rarely do as for emails and SMS I use a third party app - SafeDrive.
However, if you do get a BBM whist you are driving and you don't want to take your eyes of the road, your BlackBerry can read out the message for you and even allow you to reply - all by voice to text. Most Bluetooth headsets will allow for a 'long hold' of the main button to activate the voice services on BlackBerry 10 - so it can all be done legally.
The same rules actually apply for emails and SMS, however it only works for unread messages. If you have no new messages and ask the BlackBerry to read the last one it will tell you that you have no unread messages. On a personal note I'd like to see this changed, so the BlackBerry can still read out a BBM even if you've already viewed it. Maybe in the future.
Getting acquainted with using voice to text on BlackBerry 10 does take some getting used to, but for those times when you need to be looking at the road ahead and not at your phone it sure comes in handy.