Tropical Cyclone Sidr struck Bangladesh today with 140-155 mph winds. If Sidr had hit the U.S., it would have been rated in the upper limits of a category 4 hurricane on the Saffir-Simpson scale. According to the Weather Channel blog, the North Indian Ocean is the only place to have two cyclone seasons, April-May and October-November. Bangladesh suffered the most deadly cyclone in November 1970, killing at least 300,000 in the Ganges Delta. Another cyclone in 1991 killed 139,000. (There is a list of notable hurricanes, typhoons, blizzards, and other storms on page 303 of the 2008 World Almanac.)

Tropical cyclones are the same as hurricanes and typhoons; they are all cyclonic storms. The name varies by location. This map from the World Meteorological Organization shows the different regions for monitoring cyclonic storms as well as what they're called.

Reliefweb, a great source for emergency relief response to any disaster worldwide, said that the Bangladesh Red Crescent Society has set up 1,580 shelters and mobilized 34,000 volunteers to help with the preparation and recovery.

Bangladesh: Tropical Cyclone - Nov 2007 (ReliefWeb)
On-going Updates of Sidr (Weather Channel blog)
All sorts of cyclone satellite photos (Naval Research Academy at Monterey, Tropical Cyclone Page)