In addition to the features that were already there before like sending text messages, setting alarms, calling businesses (by saying their name), and other things...Google Now does other things, like check the traffic to your most likely next destination and shows you the travel time, traffic, and routes to get there. It does that automatically without you having to do anything. If you're waiting at a bus stop, Google Now will automatically tell you what time the next bus should arrive.
I'll leave when I think I need to, don't need Google telling me. I can always check the internet beforehand for any accidents if I'm that worried.
When your favorite team is playing, Google Now will update you with the score of the game, automatically.
The SportsCenter app does this.
If you have an appointment scheduled, Google Now will check the time it will take to get there (with current traffic), and notify you of when you should leave. Again, it does this automatically. Voice searching is just a piece of the puzzle.
I know when I have to leave, why do I need Google telling me?
[steps on crickets]
Nothing groundbreaking here.