I will say that for most trips into Manhattan I'll use public transportation (Train or Subway) just because it's easier and less subject to traffic jams. It's also just nice to read a book while traveling to work. Overall it's a less stressful experience. Almost anything in the outer boroughs I need a car to get to (Parts of Brooklyn might as well be on the moon) However Manhattan is very different then anywhere in San Francisco, whose public transportation I found mind numbingly slow and less frequent.

One place that could use some major improvement is cross-country train travel. My wife and I took a train to Montreal about five years ago and I swore never to do this again. It was painful how slow and shitty that experience was. It really wouldn't take a whole lot to improve this, the bar is that low. I would have paid more money! High speed rail will never get you to the West Coast as fast as an airplane, but if the experience and ease is worth it you can get more customers. However it doesn't seem like Amtrak gives a single good God damn. They might as well be carrying freight.