I'm open to the people I am around the most, including some of my co-workers. You have to use your discretion though; some people can't handle the information very intelligently. I haven't had much negative feedback from the people I have shared with, and work has been extremely supportive, but I do limit the information to only those people that I feel will manage the information properly. I have found more people to be able to do this than not, which has been a pleasant surprise.