One thing to consider... once you've transitioned, do you plan to remain "out," or will you pursue a more "stealthy" existence? Keeping your name can make paperwork management much easier, but my personal belief is that in transition, people need to be able to separate the old and new you. If they call you the same name, they see you as the same person, not the person that you've become. My name change signified a new beginning as a new person, but you need to do what fits your circumstances best.
Some people were resistant to acknowledging my name change, but to solve that problem, when they used the wrong name I intentionally ignored them until they got it right. Problem solved.