Do a search for some previous posts and you'll get some great detailed replies from Art Vandelay, Carol Ann, and myself. To sum things up though, Duke definitely used to be a very malignant place, but with the advent of the 80-hour rule and a new program director a few years back things have changed entirely. Now it's a very friendly and supportive program that affords a phenomenal degree of autonomy to interns and residents, coupled with top-notch teaching, an extremely diverse patient population, and a rigorous curriculum that produces outstandingly competent internists who match very well in the fellowship match. I've been very pleased and amazed at how reasonable the intern year has been, and am continually impressed at the brilliance of the residents and chiefs. I also love how we have no "private patients," and there's no special treatment. Everyone gets top-notch care, whether they're uninsured, have medicare, or a million bucks.
I hope helps. I'd be happy to answer any specific questions that you may have as well.