Wiki Fools!
Like other prominent websites and organizations (notably Google) Wikipedia likes to play harmless pranks on its users each April 1, and has every year since 2004. The first year, the notoriously deletion-happy (well, arguably) Wikipedia community took votes on whether to delete the Wikipedia main page. And though the vote for deletion was overwhelming, of course no such action was taken.
These days, some pranks are user-facing: Wikipedia now writes a humorous summary of a real article for its Featured article of the day, and in a nod to last fall's controversial banner ads (well, less arguably) featuring Jimmy Wales, today they took it a step further:
Although obviously worked out ahead of time, it still prompted a few long-ish discussions on the Talk page associated with Wikipedia's Main Page. The descriptive title of one: ""Disgraceful. Keep the April Fools Day jokes off Wikipedia!" This particular not-unreasonable argument went like this:
We are supposed to be a website of information, not mis-information. Aprils Fool's Day is not a cultural universal and it is confusing to international visitors. It's hard enough reading in a second-plus language let alone deciphering humor and sarcasm. Leave silliness to less important websites. Call me old fashion [sic] and boring but Wikipedia is supposed to be above such triteness.
The best answer, at least regarding the joke Featured summary, came from editor JTalledo:
Eh. We get into this debate every April 1st. It used to be a lot worse, when actual misinformation was placed on the main page. I remember one year there was a faux announcement about Wikipedia being sold to Britannica, resulting in an admin edit war. The current compromise involves intentionally misleading prose explaining actual facts. ... Serious events have happened and continue to happen on April 1 and they're often slighted in the Main Page hijinks. Personally, I think it's one of those things that goes against the previously stated aim of trying to achieve Britannica quality or better. But hey, it's popular, so what are you gonna do?
Yep, that sounds right. April Fool's Day may not be universal, but it certainly is international, especially in English-speaking countries. And because Wikipedia runs on Greenwich Mean Time, it's gone already.
P.S. Wikipedia also maintains a list of well-known April Fool's pranks, and it could use some assistance.