John Nack: "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." - This is a mammoth undertaking, and quite frankly, I'm not so sure it'll be worth it in the end. It's very rare for a team to sit down, rewrite a gigantor application, and succeed. Why? Think about it for a few minutes. You have a VERY successful product, millions of users worldwide. Those users expect a certain amount of continued support for the product, meaning new features, bug-fixes, etc... So, how do you split your team to deal with that effectively? Now, Adobe may already do that to a certain degree. Two teams, one working on this release, one already exploring and working on the next, then they switch positions, but what about the talk of going from being a Carbon application to a Cocoa application? These are different frameworks, written in two completely different languages. Adobe has a couple of choices here, as I see it, and probable a few I haven't considered. One, they can essentially write their own version of Carbon accounting for just the Carbon features they need, two, they can keep a portable core and write a new Cocoa front end around it. Either way, it's going to be a ton of work. The selfish, techie, side of me says "Yeah, do it, it would be awesome to work on this sort of problem. Go for it!" The reasonable side of me says "Will you sell enough 64-bit native bits to justify the cost? In the end it'll be a business decision and someone will figure out the technical hurdles, that's the way things work in the engineering world. The Sales and Marketing types always ask "Can you do this?" The answer is "Of course we can silly Sales and Marketing people, how much time and money do you have?"
I'm a bit jealous. Whoever works on this is going to have a lot of fun.
UPDATE: John notes the whole Cocoa vs. Carbon debate toward the bottom of the article. If Carbon is good enough for Apple to use in iTunes, it's good enough for anyone else, don't you think?