Variation of old hacker slang that had more negative connotations. When computer users get together and discuss things that noncomputer users don't understand. Well, first we gotta figure out if the problem's in your chips or your salsa. A section of computer code that is forever being rewritten or changed. Also can describe text documents.
Writings produced by committee are rife with churn.
Used generally to describe projects that have no more life in them but refuse to die. That disk conversion project has been circling the drain for years. A World Wide Web Site that hasn't been updated for a long time. A dead web page. A badly written or profoundly useless Java applet.