I am writing this as I sit on the train from Boston to DC. If you can afford it (in terms of time and money), I believe the train is the best way to travel between East Coast cities. It’s comfortable and stress-free. You don’t have to get to the station super early as when flying and when you arrive you’re already in the city. You don’t have to know where you’re going and pay attention to the road as when driving. And it’s less cramped and more reliable than the bus. (Not to mention more reliable than a plane in winter!). My computer is plugged in and my phone is charging. When I’m done writing, I’m going to take a little walk and stretch my legs. I only wish there was wireless, but I’m sure that will come some day. Meanwhile, I’m enjoying looking out the window. I think the view is probably considerably nicer during the winter – everything looks magical covered in snow – at least when you’re looking at it from a warm and cozy vantage point.
As for the Left Coast: I’ve taken the train from Los Angeles to Portland, OR. It was a fantastic experience (and much more scenic than back East), but is worth doing only if you will enjoy the experience for it’s own sake. If your purpose is simply to reach your destination, a plane is worth it at that distance.