At the 2007 Australian Open, Serena's been playing with a "black-label" or rather a prototype tennis racket model.  The racket is a new Wilson design which will be launched in mid-2007.  The racket head size is smaller than what Serena has played with in the past and the frame width is actually thinner than the previous models Serena has used.  Not small changes considering that a pro tennis player's racket is really one of the most important elements of his/her tennis success, i.e. one pound of string tension can radically alter the feel of a racket for many top pros.  Serena still seems to be working a bit to find that perfect feel (i.e. combination of racket, string type and string tension) because she’s switched rackets several times during her matches.  Maybe the new racket frame will become the key to Serena's (hoped for) resurgence in 2007.