From the U. S. Army Corps of Engineers, via Wikipedia:
Update: Another good blog following Katrina here. The latest information is that it may only be a strong Category 4 by the time it hits New Orleans; but they're still predicting that the damage will be catastrophic.
Update (Monday, 11:30 a.m.): From Dr. Jeff Marsters' Wunderblog: "The storm's passage to the east of the city means that New Orleans has escaped the catastrophic blow a direct hit would have delivered, and heavy loss of life is not expected in New Orleans.... Katrina is not hitting at maximum intensity and is sparing New Orleans a direct hit, and although the damage will be incredible, it could have been much, much worse." Thank God!! Although what has happened looks terrible enough.