Apple released Shake for OS X:
Shake 2.5 will be available for Mac OS X for a suggested retail price of $4,950 (US) with annual maintenance of $1,199 (US), and for Linux, IRIX and Windows for a suggested retail price of $9,900 (US) with annual maintenance of $1,485 (US). Existing Shake customers will be given the option to double the number of their existing licenses at no additional cost by migrating to Mac OS X.
Apple appears to be aggressively trying to attract new users to the Mac platform with this sort of aggressive pricing. Note that Shake cost $9,900 prior to the Apple buyout, and the $4,950 OS X pricing is a discount of the OS X version... and not a markup on the Windows/Linux versions.