In the US, there is a possibly of parole, whatever or not the person gets it depends on certain things (ie behavior in prison and even celebrity status can have an effect on it). It says that he can be sentenced to 60 years, but it may not be 60 years due to either a plea bargain (less time and reduction of charges) or the judge's decision based on crime itself and previous convictions/pleas.

Let's give this situation a what if sernario. If Gary McKinnon hacked into his own nation's (UK Ministry of Defense) military computers instead of a foreign nation's (US Department of Defense), he would been charged with treason and that is one of the worst crimes that a person can commit.