It is a legal accident that corporate personhood was established in the first place. http://www.straightdope.com/columns/read/2469/how-can-a-corp...
While corporations are not flesh and blood people, we as humans can certainly define intangible entities into existence. They are still made up of people, but that does not diminish the realness of an entity created only by our civilization's power of words and ideas.
I think people should have rights; not inanimate entities. I think corporate personhood is one of the most egregious mistakes ever committed by humanity as it has allowed living people to no longer be accountable for their crimes. I also think it's too late to fix -- if the USA eliminated corporate personhood, the stock market would crash and there would be a mass exodus of corporations to more business friendly countries.
It's not a hopeless situation though; there will continue to be restrictions on the rights of corporations. I'm optimistic that Congress is going to overturn this most recent Supreme Court decision.
We could be doing more. As an important first step, I suggest a drastically increased use of the corporate death penalty, starting with multiple-time convicted felon (and statistical mass-murderer) Pfizer. If Pfizer was a flesh and blood person, it would be spending a very long time in prison. Instead, it has only paid some of the largest criminal settlements in DoJ history. http://en.wikipedia.org/wiki/Pfizer