[4258HzG]

Given current IP law, I think the more relevant question is how public Universities should handle their patents (e.g. for public use, for a nominal license fee, or profit) and not if they should patent.

A non-existant or poorly executed patent allows for anyone to follow up, as MIT/Harvard in this case, and effectively patent minor extensions to the idea and still lock it up. Even if a public university wants their inventions to be free to the public, they need to properly patent it if it is going to stay available for public use. Eg. BSD style licenses for patents.