That is a very interesting finding. But of course one would have to correct for the factors affecting this statistic that are independent of BlackBerry use per se to get a more accurate estimate since business in general must have been affected greatly.
I'm not surprised though - in the wrong hands (as they often are) cellphones are deadly. Every day of the year. There's plenty of hard data to prove that (cellphone logs at instant of impact ...).
Maybe we should have a mandated national shutdown of the cell phone networks around rush hours. Of course, that would delay people calling for help after getting hit by idiot motorists. Maybe a shutdown for everything except 911 around those hours?