Jamz was the only urban station to see a significant drop, so it must be the fault of diary placement? Um, I'm no radio insider but that's a bunch of malarkey.
Tornadoes do not discriminate against one race. Even though the B'ham tornado did tear through some majority-black parts of town, in the grand scheme of things it only affected directly a small percentage of the population. I would find it hard to believe a bunch of diaries were scattered along that exact path through Pleasant Grove (only about half black I think) and Smithfield (mostly black).
Frankly, I find the allegation a little distasteful. Not that Arbitron isn't voodoo or may screw up in the wake of a disaster, but the evidence just seems like weak sauce. To wit, WTUG, Tuscaloosa? Up. Kiss FM? Up in B'ham and Tuscaloosa. Hot 107, WAGG? Steady. Not exactly damning evidence of diary manipulation, there.
Branch out a little: ZZK, Magic, Jox, all down, too. Not exactly urban stalwarts, these.
The truth is the stations that engaged the audience the most in the recovery effort probably saw a bump. WAPI-FM doubled its previous book in Tuscaloosa. WERC was up in Birmingham. Kiss FM, The Q, WJRD-AM, all saw big bumps and I bet they all worked the recovery effort more than Jamz. Maybe I'm wrong, though — I did not listen to Jamz after the tornadoes. I streamed WAPI and their totally live and local day coverage was very good.
Finally, if Birmingham's book is wrong because of its tornadoes, surely someone should be calling for a cancellation of Tuscaloosa's book as well? T-town was hit MUCH harder overall than Birmingham. And yet, urban did fine there.