Yep, Solaris/CDE had a Dock long before Mac OS X came along. No need to shout "copy!" here. And I'm pretty sure that the 3D window effects don't stem from Exposé but from the basic idea of a 3D desktop.
(You'll find a screenshot from RacerX showing a CDE desktop with the dock -
http://www.macfora.com/forums/index.php?act=Attach&type=post&id=238651 - here...)
Makes me wonder what Mac OS X will look like in, say, five years from now, though. And whether we will scream 'copy!' at it, because it took some 3D fx from SUN's and Microsoft's ideas...