I am not an expert, but between 100,000 and perhaps far more human beings are at risk tonight in Bangladesh and Western India near Calcutta. Sidr is currently at the high end of the scale for a Category 4 hurricane and heading towards the New Orleans of the world, Bangladesh. The latest news I can find on this is from bloomberg and thedailygreen. The belief is that the storm will weaken as it hits shore, but currently there is a 40 ft storm surge heading towards flat land populated by millions.
Edited to add: Excellent diaries are at alefnot and here firshoutof water, sorry I could not find them in my original search.
When I saw these early reports from the Bay of Bengal, I though of the diaries prior to Katrina. I vaguely remember the cyclone that hit Bangladesh in 1970 which killed between 300,000 and half a million people (the Concert for Bangladesh was in response), and there was a 1991 cyclone that killed over 100,000. I don't quite know why I am compelled to write this diary, except the sheer magnitude of this threat just stops me in my tracks and puts all of my day-to-day worries into context. If someone else knows more, please let us know. Let's all hope and pray that the storm's fury abates.