It has been a long time since I smelled a rotten egg. But I read an article recently explaining that some of the newer homes have that odor coming out of the walls.
It is normal in some older homes for the water to have some sulpher (hydrogen sulfide gas actually) smell in the water, and according to government sites exposure to this is not dangerous. In fact, exposure to a little bit of this gas is said to be good for you. In one study they apparently injected low doses of the stuff into heat attack victims to try to prevent tissue damage.
However, in newer homes if the smell is coming from the walls then it could be a warning of gas emissions at a level that is damaging not only to people, but also to expensive appliances such as air conditioning units and microwave ovens, or even to jewelry. One link with more information about this problem is http://www.chinesedrywallproblem.com and also various other groups are starting campaigns to advise the public on the problems.
Homeowners in Florida, and some other states have experienced unacceptable levels of hydrogen sulfide gas emissions which have destroyed copper coils and even nails and screws. Upon investigation, it was found that coal ash had been added to the gypsum in the dry wall. This causes a bad chemical reaction that apparently has resulted in some infant deaths. The elderly are also at risk.