The Intel 64bit version of Photoshop CS4 will only be available on Windows… as in, no 64-bit Macintosh version. Yeah. I said the same thing too.
‘Whoa.’
Quoting the blog article of John Nack:
What’s Adobe doing with Photoshop? In the interest of giving customers guidance as early as possible, we have some news to share on this point: in addition to offering 32-bit-native versions for Mac OS X and 32-bit Windows, just as we do today, we plan to ship the next version of Photoshop as 64-bit-native for Windows 64-bit OSes only.
John goes on to explain that they will eventually ship a 64-bit version at Photoshop CS5 in the future however, as of right now, there’s not going to be a 64-bit Mac version of CS4.
Why?
As we wrapped up Photoshop CS3, our plan was to ship 64-bit versions of the next version of Photoshop for both Mac and Windows. On the Mac Photoshop (like the rest of the Creative Suite, not to mention applications like Apple’s Final Cut Pro and iTunes) relies on Apple’s Carbon technology. Apple’s OS team was busy enabling a 64-bit version of Carbon, a prerequisite for letting Carbon-based apps run 64-bit-native.
At the WWDC show last June, however, Adobe & other developers learned that Apple had decided to stop their Carbon 64 efforts. This means that 64-bit Mac apps need to be written to use Cocoa (as Lightroom is) instead of Carbon. This means that we’ll need to rewrite large parts of Photoshop and its plug-ins (potentially affecting over a million lines of code) to move it from Carbon to Cocoa.
So there you have it.
Taken from http://blogs.adobe.com/jnack/2008/04/photoshop_lr_64.html
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