I don't have any regrets or complaints after driving the Altima Hybrid for 2 months. The best mid-size exterior styling, pretty nice interior. MPG is right inline with EPA estimates. My only beef is that it does seem a little heavy. Adding several hundred pounds of batteries between the rear wheels makes the back end a little heavy when corner, but hey, it's a hybrid, so don't expect a sports sedan. Great car.
Smart Key - handy when carry the kids to not have to fumble for a key.
Add additional trunk space. The Camry makes the most of the trunk, the Altima doesn't. Car should automatically shutoff if left on for more than 20 minutes w/out shifting out of Park. Stiffer suspension, the front end really rises and dips under moderate acceleration and braking.