Comment The visa issue (Score 3, Informative) 78
Accually, I was detained for a few hours some years back over the same issue. The visa waiver thingy means you can't accually -work- while being in the US, you can interview people, write articles etc., but you can't publish anything -while- you're in the US. For this you need a special visa or something, which I didn't have, and I suspect the French journalists didn't have either.
The kind officers of the US Immigration Service (or something) eventually let me go, but they could've easily put me on the first plane back. Or body searched me a few times, detained me for 24 hours and -then- put me on a plane.
After this incident, I never ever ever get into specifics over what kind of work I'll be doing at E3. I suspect the French journalists may have answered 'mais oui, i will publish my articles while I'm here' for all this to have happened. I also suspect the fact that they're French didn't exactly get them any favours.