Adobe Systems has shared the first scrap of information about its next version of Photoshop, CS4, and it’s a doozy: there will be a 64-bit version of the photo-editing software, but only for Windows and not Mac OS X.

Adobe generally keeps features in the Windows and Mac versions at a level of parity, but that wasn’t possible this time around because of a change Apple made last year to the Mac’s programming underpinnings, said John Nack, Adobe’s product manager for Photoshop, in an interview.

“We’re not going to ship 64-bit native for Mac with CS4,” Nack said. “We respect Apple’s need to balance their resources and make decisions right for that platform. But it does have an impact on developers.”