Google Now is pretty awesome, and even on the N7 I've found it to have some value. For example it has noticed that I drive from home to work daily, and I assume if traffic ever was an issue it'd let me know. Also it's notified me of a storm once which was neat.
The only thing I've found that was abit off is last week while planning an upcoming trip I mapped out a route from a hotel we're staying at next week to a restaurant, then searched for a few other destinations in Google Maps... all this from my laptop. Then Google Now that evening on the N7 started sending me traffic updates from those locations. Not a huge deal, but something odd.
But all and all I'm anxious to see where this technology goes and how it'll evolve, not only short term in Jellybean but long term as well.