Here is an article: Jones Act complicates messy situation for Obama - about the oil spill and the Jones Act which I think is more or less accurate. It is from Mr. Bluey, a contributing editor to Human Events, is director of the Center for Media & Public Policy at The Heritage Foundation.
On the other hand I believe that this article from The Christian Science Monitor, which I have until now considered to be a trustworthy source, is incorrect. Jones Act: Does Gulf oil spill cleanup need more foreign boats?
The CSM article has this incorrect information in the header.
The Jones Act prevents foreign skimmers and tankers from helping with the Gulf oil spill cleanup.
The Heritage Foundation article on the other had says this:
Because the law only covers a three-mile limit from the U.S. coast, foreign ships do not have to get a waiver to work near the site of the spill or other areas in need of skimming.
Not sure if that is exactly correct but my understanding is that the Jones act does not prevent oil being transported from the Gulf of Mexico to a U.S. Port.
I think that the source of the misinformation are sources which oppose the Jones Act for other reasons and are using the BP Deepwater Oil Spill as an opportunity to push forward their agenda. An example is (From the Heritage Foundation article)
Newly elected Rep. Charles Djou (R-Hawaii), who raised the issue during his recent campaign, vowed to introduce legislation exempting Hawaii from the Jones Act because it has reportedly resulted in higher costs for goods.
Deepwater's; - Cabotage and the GOM