Around July last year, word on the internets had it that Joaquin Phoenix was attached to Charlie's other mysterious project -- the one about world leaders who gather, all top secret like, to plan the world's big events (oil prices, wars, yadda yadda). In October, word spread that Carey Mulligan might be on board as well.

Today Deadline reported that Samantha Morton and Amy Adams are circling the project as well. BUT! HOWEVER! Deadline later updated that report, and the update goes like so:

Sources tell me that the project that Morton, Adams and Mulligan and Phoenix are doing was written by Spike Jonze himself, and not Charlie Kaufman. The film is about a guy who falls in love with the voice of a computer, similar to the Siri feature on the new iPhone. (Source)

(Emphasis added by me.)

You can read the original announcement of Morton and Adams' involvement at the "source" link above, too.

In conclusion: I DO NOT KNOW WHAT IS GOING ON. I am just a humble Aussie boy. I reports what I hears.

Thanks to Ujwal for the heads up, and Sreehari.

Additional information