Apparently you people don't a) keep up with Apple and Adobe news b) understand very little about the software development process.
Adobe was full set to have CS4 have 64-bit support in OS X however about a year ago at WWDC '07 Apple told developers that they were pulling the plug on Carbon 64-bit support, responding to cries that Carbon is officially DEAD as a future development platform by telling them Cocoa is the way to go. Now, Apple's been making it pretty clear that Cococa was the future and Carbon was a stop-gap solution but even Apple themselves taut Carbon as better for cross-platform development.
Since Carbon won't ever be 64-bit, rewriting the entire suite of CS tools would take more than a usual update cycle to switch from Carbon to Cocoa AND make the app 64-bit compatible. That's just a ******** of bug testing and not enough time to do it while releasing the Mac version at the same time as the Windows version. So instead Adobe is going to work on porting their Carbon code to Cocoa (which means a rewrite of C++ code to Objective C) in CS4 and then add 64-bit support in CS5.
Though you might want some proof, so here's Adobe's blog annoucement:
http://blogs.adobe.com/jnack/2008/04/photoshop_lr_64.html