I hiked a portion of that trail back in 1978. We started in NY State and hiked for three days and I forget how many miles, but we were so sick of packaged trail food that we got off the trail and hitched a ride to the nearest tavern for burgers and beer.
We had alot of fun, and met some nice people. I would love to do it again.
My brother is going this saturday to VA up through MD and to the begining of PA. He will be gone for seven days will a buddy that wanted to go with him as well. It will be cool espcially the first couple of days its suposed to rain. But it sounds so fun and i am jelous that i don't get to go.
I've read that parts of the trail usually through mountainous areas can be pretty rugged and some areas aren't very well-maintained. Most people starting in the Spring start on the southern end and work their way north. If your brother is an experienced hiker I'm sure he will know how to dress appropriately. If not, he should probably do some research on the subject.