The killer was an angry white male. (There were two of them and they were black.)
The killer was acting alone. (See above.)
The killer was a right-wing gun nut. (Louis Farrakhan and the Nation of Islam are not right-wing.)
The killer was using a white delivery truck/white van with a ladder. (They had a dark-colored Chevrolet Caprice sedan.)
The killer was avidly watching the TV coverage of the slayings. (They were living in their car.)
The killer just happened to be operating near the federal capital. (They made a cross-country trip from Washington state to get there.)
The killer was working some kind of a regular job and doing the killings in his spare time. (They were unemployed.)
The killer was a courier or delivery driver familiar with the area, enabling him to cunningly escape after each murder. (Neither of them had lived in DC, MD, or VA before.)
The killer had military sniper training. (Muhammad only had basic training - he was a U.S. Army machinist.)
That's basically just off the top of my head. I didn't watch a great deal of the sniper "coverage", so others may be able to add a some more points. What I'm trying to show is that the media speculation was not just a little off - it was complete and utter nonsense. Linda Chavez is much too kind.