TIME magazine does a good job of answering the question in this title, The Stolen E-Mails: Has ‘Climategate’ Been Overblown? Highly recommended.
The short of it is yes, it has been overblown.
If you are a skeptic of global warming, good for you, if you apply the same skepticism for anything you hear from the scientific community. Good scientists are skeptics themselves, and challenging what scientists put forth makes for better science.
If you are convinced that global warming caused by people is true and terrible, then I think this setback is actually a good thing, even if in the short term it may not seem that way. I believe this is true, namely, that “climate scientists and advocates will need to rethink how they engage with critics. Judith Curry, an atmospheric scientist at Georgia Tech, wrote in a much-discussed blog post that researchers need to make climate data much more open and transparent, and that scientists need to be wary of falling into what she calls “climate tribalism.”” I am a strong proponent of open data and open systems, and trying to close down the discussion leads to bad science and bad politics. I hope the climate scientists come at this with even more rigour and more force. The forces against them are going to be there whether or not they are open and practice good science or closed and practice bad science: the aim should be for more transparency and more research.