According to one source, Apple will finally be releasing the Universal version of Shake (4.1) tomorrow. Alongside it will be a significant price drop, rumored to be $499 (down from $2999).
The future of Shake, however, would be in jeopardy, as the 4.1 release is said to be the last release with scale backs in the development team. The demise of Shake, however, would be relieved by another high-end compositing application not due until 2008.
There have previously been reports of a high end "Final Cut Extreme" application in the works.
Update (moved to page 1): As rumored, Shake 4.1 (universal) has been released, with a significant price drop as expected (now $499 USD). There are no official indications that this is indeed the last major release of Shake beyond Apple not continuing its maintenance program, but that does not preclude the possibility, as Apple may still want to sell the reduced-priced compositing software until their new high-end solution is available circa 2008.
Update 2: According to Shake users who have contacted Apple regarding software maintenance issues, Apple states that users will be unable to receive further updates for Shake as development has been focused towards the "next generation" of the application. Partial quote below, with full quote in the thread.
Apple will no longer be selling maintenance for Shake and no further
software updates are planned as we begin work on the next generation of
Shake compositing software.
According to our source, this "next generation" program is not based on Shake code, but rather is based loosely on Motion code, which may explain why Apple is licensing Shake code to select Maintenance customers for $50,000.