tl;dr version ->
If you are concerned with the U.S. government seizing your domain get a TLD from Switzerland(.ch)
See https://www.pirateparty.ch/wikileaks_ch_blocked (EveryDNS stated it isn't taking a position on the content hosted on the wikileaks.ch website)
In addition, I'd like to say that I don't think there is a problem with .com, .net, or .org
It's way more important which registrar you have.
As far as user-generated content, perhaps this is a nod to policing that content much more unless you have the resources to handle legal challenges that will almost inevitably come up.