Sentencing guidelines

Justice O'Connor wrote that the Blakely decision could undermine sentencing guidelines as such. Many commentators and journalists seem to agree. For example, Mark Kleiman offers this preliminary assessment:

The Court held, in effect, that old-fashioned discretionary sentencing, under which the judge imposes a sentence between extremely wide limits set by the legislature (e.g., “not less than one year, nor more than twenty years”) is fine, but that guideline sentencing, under which the judge makes findings of fact and then, based on them, imposes a sentence between very narrow limits set by a sentencing commission, isn’t.

Yet, Blakely's sentence was deemed inappropriate because judge defied the sentencing guidelines, not because he observed them. According to a recent CNN article entitled High court ruling casts doubts on sentencing guidelines:

A judge had said Blakely acted with "deliberate cruelty" and deserved a longer prison term than the four years set out in state sentencing guidelines.

Maybe the issue is whether sentencing guidelines are really guidelines, as opposed to rules.