My dad paid for business class seats, which I highly recommend. The leg room is beyond the wildest dreams of airplane travelers and the seats actually recline enough that you can take a nap. The ticket includes a free soft drink from the cafe car (which is pretty comparable to a concession stand at a high school sporting event) and there are convenient power outlets next to each pair of seats.
Yes, it takes longer to travel by train than to fly, but there is so much less hassle that your patience is amply rewarded. There's no need for early arrival, no baggage screening, no waiting in line. You show up at the station, sit in the waiting room until the train arrives, go outside and get on board.
The train stops briefly from time to time, but bypasses any stations on the route where there's no one interested in getting on or off.
On my trip out, it was dark most of the time so there wasn't really anything to see out the window. I read an entire book and goofed around online with my phone when we were close enough to a populated area that I could get phone service.
On the way back, it was full daylight so I spent some time looking at my surroundings. It turns out that it's very difficult to tell where you are from the train, even if you're in a familiar area. There are almost no signs for train passengers except when you're near a station, so you have to look for distinctive landmarks. I read another whole book on the Kindle app of my iPhone and started a second one.
Only if you're hoping to impress someone with the glory of the United States would I not recommend taking a train trip. Much of the scenery was pretty grim: junkyards, disused industrial areas and collapsing farm outbuildings were the norm. The Amtrak galley employee said he passed the time by looking for eagles, which I could appreciate because I like to keep a hawk and eagle count when I'm a passenger on cross-country road trips.
I'm not sure when my next train trip might be, but I'm considering it for BlogHer this year in Chicago. It would be an ideal way to keep the stress down on the way there and decompress from the conference overstimulation on the way back.