There's kind of a global taboo on talking about poop. [You wouldn't know that hanging out at our house, with two boys aged 8 and 5, but it's true.] The reluctance to talk about sewage, latrines, and toilets has put the cause of improving sanitation in the world's poorest countries years behind where it should be.
2008 is the UN's International Year of Sanitation (did you know?), and in Stockholm last month leaders described the challenges ahead in improving sanitation systems for the world's poor. In contrast to clean water provision, sanitation has lagged behind. This year, the number of people without access to clean(ish) water is down to less than a billion (the number was 1.4 billion last year). Half the world's population now has a pipe with improved water coming into their house.
However, 2.5 billion people still lack adequate sanitation systems for their families, resulting in millions of premature deaths every year from diarrhea and other related diseases. Prince Willem-Alexander of the Netherlands reminded the Stockholm gathering that "it is hard for [people with fancy flush toilets] to imagine how unsafe — not to mention embarrassing — it is to relieve oneself in public, in the middle of the street, or for women in rural areas waiting for sunset to find a bush or faraway field, with high risks of physical assault or rape."
Christian ministries like Tearfund have taken up the challenge of providing such systems and in advocating for increased aid funding. You can read their report on the global issue, called "Sanitation Scandal" at their website.
Also, Jeff and Darcy Anderson with Lifewater International maintain a great blog called "When you gotta go". You should go check it out. It's great bathroom reading.