After SPIN! Video: What guidelines should we have for naming rights?

After SPIN! "Question to Greer Beaty – Over the past few years we’ve seen a big increase in the number of corporate and private sponsorships and naming rights for public arenas, parks, museums and buildings. Is this primarily because we aren’t providing sufficient funding for this public infrastructure? Are these sponsorships and naming rights cheapening our public facilities? Should these naming rights expire after a certain length of time or be permanent? Should some businesses or products be prohibited from participating? What guidelines, if any, should be established?"