The article on Christmas is set to be on the Main Page on December 25th.
It used to be Featured quality. That was a year ago. Since then, it has had 600 major edits, 500 other edits, and is nearly unreadable.
Compare the originally Featured version to the current version: http://en.wikipedia.org/w/index.php?title=Christmas&diff=32012542&ol...
Now, it is up for FARC: http://en.wikipedia.org/wiki/Wikipedia:Featured_article_removal_candidates/C...
To prevent stagnated articles from being presented as "top quality" on the Main Page, there seems to be two solutions: set a time limit for Featured Articles, which requires them to be renominated on FAC if they become too different from their original Featured versions; or, implement the "stable article" option that Tim Starling has talked about, which would allow admins to set a "last good version" to be presented to the public at all times, while the real version is somehow edited "behind the scenes". As productive edits pile up, admins can set a newer version as the "last good version". While this can still result in an article being drastically-changed, it is much more likely to be changed for the better in the long run.
brian0918