Where did you hear that? March 4 would be odd, since it's a Monday. Usually they start releasing them over the weekend.
USUALLY it starts this weekend (the last one in February.) Like 5 out of 7 years that is the rough time frame. Last year, however, they did release the week after, into the first weekend of March. So if absolutely none of us hear back by Monday, likely things were delayed, again. That puts it at like 95% change they'll start getting issued next weekend. Anything beyond that, and we are in the area of the unknown, as letters have never failed to at least start going out past the first weekend of March. Then again, last year, denials were released at a record late date, so not out of the realm of possibility same could happen with acceptances.
Personally? My gut says we'll start hearing back this weekend. But, hey, my gut has been wrong before. Like, say, the two times it told me "You should TOTALLY apply for USC, there's no way you wouldn't get in!" So the bastard is a liar, is what I'm saying.