The Wall Street Journal (sub required) describes boom time in rail freight
"North America’s major freight railroads are in the midst of a building boom unlike anything since the industry’s Gilded Age heyday in the 19th century—this year pouring $14 billion into rail yards, refueling stations, additional track. With enhanced speed and efficiency, rail is fast becoming a dominant player in the nation’s commercial transport system and a vital cog in its economic recovery."
In the last couple of years I have cataloged quite a few entries on how tech is redefining rail
GE's locomotive innovations with fuel cells and software optimized speeds
Experimentation with long trains (like 3.5 miles long below) and placement of locomotives in front, back and middle to prevent derails (called Distributed-power units - train below has 3 locomotives in front and 2 at back)
Optimized dispatching at Norfolk Southern