There was a nice mention of the I&M canal trail in National Geographic Adventure magazine's "Next Weekend Escapes" feature in the June / July 2009 issue. 

The I&M and the Hennepin are just a portion of the northern route of the American Discovery Trail, a coast-to-coast east-west route of connected trails designed for hiking, biking, and equestrian use.  Much of the American Discovery route is comprised of trails like the Hennepin, in that they are off-road--this is in contrast to the great road routes from the Adventure Cycling Association (ACA's routes typically utilize roads and highways, with the exception of ACA's Great Divide mountain bike route).  There is an effort to make a north-south network of trails similar to the ADT called the East Coast Greenway. 

From an afternoon outing to an epic transcontinental journey, the trails and routes are a great resource.