Just got this from Brian Graham, Hammer Brand Manager (he was out of the office last week):

"The black marks are not plug marks.  They are impact marks that are caused during shipping and during our manufacturing process as the balls roll down the production line.  The Black Widow coverstock is extremely aggressive and is susceptible to phasing (when the coverstock lightens in color).  Once the ball hits something, it will leave a dark circle or mark on the ball.  Once the ball has been thrown a game or two, the marks will disappear.  The impact marks will no affect on the performance of the ball."

MatchARing and Pinhammer are correct.
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Ken
Defender of the logical thinking center. I have no time for extremists.
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