https://blog.wikimedia.org/2012/01/16/wikipedias-community-calls-for-anti-so...

"...the Wikipedia community has decided to black out the English-language Wikipedia for 24 hours, worldwide, beginning at 05:00 UTC on Wednesday, January 18. The blackout is a protest against proposed legislation in the United States —the Stop Online Piracy Act (SOPA) in the U.S. House of Representatives, and the PROTECTIP Act (PIPA) in the U.S. Senate— that, if passed, would seriously damage the free and open Internet, including Wikipedia....."

We'll be disabling editing via the web service API. You can ask questions regarding the planning in #wikimedia-sopa .