So here's that original ABC News story, which is a Reuters wire story, not an opinion piece.

Here's one from the LA Times:

Laptop seizures at customs raise outcry
I pulled this quote out of the article: "Of the 100 people who responded to a survey the association did in February, seven said they had been subject to the seizure of a laptop or other electronic device." Not inspection. Seizure.

Another quote: "Courts consistently have ruled that there's no need for warrants or suspicions when a person is seeking to enter the country -- agents can search belongings, including computer gear, for any reason."

And another one: "Any routine search is considered "reasonable" under the 4th Amendment, legal scholars agree."

Here's one from the San Francisco Chronicle in April outlining an appeals court case that gives the okay for customs to search through travelers laptop contents.

And here's one from the New York Times going all the way back to October of 2006, suggesting this has actually been going on for quite some time.

A lot of the evidence and news stories are anecdotal because the travel forums and blogs have been talking about this for a long time. But that Reuters story from just a couple of weeks ago is pretty hard to ignore.