According to the National Enquirer:

The controversial country superstars have secretly decided to split up after the Grammy Awards - because Emily Robison and Martie Maguire no longer want to share the nest with outspoken Natalie Maines, say sources.

“The Chicks are tired and wrung out,” said a group insider. “They feel they’ve come to the end, and they want a break from each other to spend more time with their families.”

The three women, who have seven children among them, are at odds over Natalie’s blunt political ramblings. And while sources say sisters Emily and Martie share many of Natalie’s anti-George W. Bush views, they feel her public rants have taken the focus off their music.

“They’ve supported many of her political beliefs, even though it’s put their lives and the lives of their families in jeopardy,” said the insider.

Yeah, I know.  The Enquirer ain’t exactly a reputable source for solid journalism, but the article does serve as an excuse to post this funny skit from MadTV:

If the Chicks do break up it’ll actually be sort of sad.  Watching their careers crash and burn after Natalie so forcefully thrust her foot into her mouth and alienated much of her own fan base has been hilarious entertainment.

Much better than any of the music they came out with.