After the Rich pardon President Bush made a big deal about following the Department of Justice guidelines and my guess is Obama will feel pressure to make a similar promise.
I hope Obama does not make that promise. According to the Department of Justice guidelines pardons should be given only after a substantial period after a conviction (usually at least 5 years) and meet a list of criteria that include genuine remores, good conduct, and the opinion of Justice Department official and judges. All of these are only suggested guidelines because the President's pardon power is absolute as guaranteed by the Constitution in Article II section 2.
However, I fear great pressure to follow the DOJ guidelines will be placed on Obama. That's too bad. The DOJ is the federal government's police and prosecutorial arm. The DOJ in its police, prosecutorial, and punishing function is, in the words of Josh Marshall, "a vast, impersonal, crushing, and awful thing." For a good example of this crushing and awful power look at the number of non-violent drug offenders languishing in prison. To have the police and prosecutors in charge of granting mercy only ensures that not much mercy will be granted. A separate party needs to be able to mitigate harsh punishments and add a leaven of mercy to our justice system to ensure that it is truly a just system.
I am willing to trade the occasional odious pardon if the President would freely grant a lot more of them to deserving people.