News accounts say that Judith Clarke,who formerly represented the Unabomber, will represent the Arizona shooter, Jared Lee Loughner. Legal ethics types may recall that the defense of the Unabomber was quite controversial, in that some believed the defense lawyers usurped their client's decision-making and deliberately kept him in the dark until the very last minute. That version of the story can be found in the long piece by William Finnegan in The New Yorker (sub. req'd). (It's a great reading for PR classes, btw.)
At the same time, Clarke and her co-counsel in the Unabomber case, Quinn Denvir, have the highest of professional reputations and I've heard criminal defense lawyers make very strong defenses of the choices Clarke and Denvir made in that case. If you're really interested in the issues, you might read some of the work of the late Michael Mello (Vermont).
In the Arizona case, my sense is that the evidence of severe mental health issues may prevent the replay of the Unabomber case.