Hi, I'm the author of the extremely innovative FontCard and this is a follow-up, of sorts, to my previous post about the Intel-chip based Macs (ICBMs). This post is confined within the set of applications available for a platform. It does not consider the operating system running the applications at all. Some people believe applications make the OS and others believe the OS makes the applications. This post targets the former.
As I see it, when Apple starts shipping ICBMs and (heaven forbid) the PowerPC is deprecated then those requiring backwards compatibility have two primary choices:
As far as I am concerned, a huge issue for consumers when buying a new machine is whether or not their existing applications work. Many people still run applications made around 1985 on OS X using the Classic environment. There are many applications that were made for Mac OS 9 (meaning any version of the Mac OS before Mac OS X, including System 6.0.7 and the like) and were either never updated for OS X (possibly because the developer went bankrupt, was bought out, or just died), the developer charged too much for an upgrade, the upgrade required too many other changes, or the upgraded version was too different from the classic version to train people on. Apple lost a lot of sales to education because of the switch to OS X. Many education entities couldn't afford the cost of upgrading their software to native versions, so there was much less incentive to purchase new machines from that but even if they did buy new machines (like from a bond issue passing) then they could still run their educational software on the new computers. If educators bought new ICBMs, they won't be able to run their classic education software as Mac OS X running on Intel machines does not support classic.
Aside from Classic compatibility, there is a problem with running newly released applications on ICBMs as well. Rosetta (Apple's solution for running some PowerPC applications on ICBMs) will not run applications that require a G5 processor. At WWDC, Apple displayed the Intel-based Mac running Adobe Photoshop CS2 in an emulated process. It was noticeably much, much slower than PS CS2 running natively on a PowerPC based Mac. Adobe PS CS2 requires a PowerPC G3 or higher. Let's not forget Apple's own Pro software. All of it requires a PowerPC G4 or better. The Final Cut Studio itself requires a PowerPC G4 at 867MHz or faster. Whereas Final Cut Pro 5 itself requires a 500Mhz G4 or faster. Apple has taken the option of not permitting those applications to run under Rosetta. Apple "just" released these applications and they won't run on the ICBMs at all. While Steve Jobs was showing off iPhoto zooming at the WWDC Keynote (00:26:36 into it), an audience member asked "What about Final Cut [Pro]?". The audience laughs and Steve Jobs just shrugs it off. His reaction leads me to strongly believe he heard the comment. I was in the back of the keynote room and I clearly heard the comment. It isn't very audible on the stream, however.

Some application developers, such as Apple and Adobe, are using this switch to "extort" money out of their users. Apple is charging $29-$699 in order to acquire the Fat versions of its various Pro applications. Now, there is nothing technically keeping these applications from running in Rosetta since they all fit within the maximum application requirements for Rosetta. Apple has, however, chosen to require that users pay more money in order to get a version that runs on the ICBMs. What's even more insulting is that they say making software work on the ICBMs requires just a simple check in a checkbox. Not that it is actually that simple, but enough users have believed it that we've received emails suggesting that porting APE should only take a day. Luckily, we have a strict non-strangulation policy in effect at Unsanity. This is definitely not a new method of "extorting" money for Apple. They've done the same thing with previous versions of Final Cut Pro. Final Cut Pro 4.5 refuses to run on a non-AGP Mac. This means you could not install it on older Macs. However, there was a simple work-around for this. This also means that Final Cut Pro 4.5 won't run on PCI Express Macs. Apple's recommendation for this is to "upgrade to Final Cut Studio at a small, $199 fee". Adobe has a slightly more valid excuse as they never once said or implied Adobe Creative Suite was a checkbox away from working on the ICBMs. Furthermore, they didn't "artificially" disable any part of the Creative Suite on the ICBMs. Adobe's very official response says they will charge users an upgrade fee for a Universally Fat version of the Creative Suite. More importantly, they've stated they will not be releasing Universal updates for their current product suite. This also applies to products from Macromedia, as Adobe totally pwn3d Macromedia. Many other application developers are also making minor updates to their products that refuse to run under Rosetta until they made a paid for update that will run natively on the ICBMs.
There's also an issue for applications that host plugins. Plugin hosts such as Adobe Photoshop, Adobe Illustrator, Corel Painter IX, QuickTime, browsers, AppleScript, Application Enhancer, and others must have their plugins match their host application's architecture. Rosetta does not support anything like the Mixed Mode Manager. Some of these plugins can be quite pricey, around $750 US per user, and there is no indication on whether or not companies that produce plugins will charge a full upgrade price for a x86 native version of their plugins that run on the ICBMs under the possibly forthcoming native versions of their host application. To handle this potential problem and incompatibility, Apple has introduced a application property list key that forces the application to run emulated on ICBMs. However, this option greatly reduces the performance of the application and its plugins. The applications that will suffer the most from this plugin-must-match-host problem are the multimedia applications, especially ones that use QuickTime to import, export, and playback video (such as Adobe After Effects and Final Cut Pro) since QuickTime will run as non-native in non-native applications. And video performance will suffer greatly since the installed QuickTime component for a particular video format (such as 3ivx) must match the host application if that host application is PowerPC because emulation programs, such as Rosetta, cannot handle the architecture of some new codecs (such as H.264) too well.
General consumers might run into problems while browsing the Internets, also due to the plugin-must-match-host problem. If you don't have a Universal née FAT version of an internet plugin installed (such as RealPlayer or Windows Media Player) and you go to a site that has content that requires a plugin, you may no longer be able to view the content of the site. For example, there is currently no Intel native version of RealPlayer or Windows Media Player, so if you wanted to watch some fair and balanced CNN Video on an ICBM using the native version of Safari with the respective plugin, good luck. Luckily if you wanted to watch a Strong Bad Email using the native version of Safari on an ICBM there is a fat version of the Flash plugin pre-installed. Hopefully, Real and Flip4Mac will release an updated version of their respective plugins soon. This problem also extends to any application that uses WebKit (such as NetNewsWire) and supports content which requires a plugin to display. Another good example is Contextual Menu Plugins. If you use something like Stuffit Deluxe 9, you won't have the right click functionality in the Finder. I'm not sure if they've released an update for Stuffit Deluxe 10 as I do not own that version.
Let's not forget that Apple doesn't exactly have the best backwards or forwards compatibility. And what little support they do have quickly disappears. For example, Classic/Mac OS 9 was quickly unsupported. First, with Apple no longer including Mac OS 9 with Mac OS X. Then, with them no longer supporting Mac OS 9 with any of their first party applications. Finally, they suggested to all third party developers that they drop support for Mac OS 9. I imagine the same thing will happen with the PowerPC Macs 6 to 12 months after the "transition" to Intel is complete. In fact, Apple may drop support for their Pro applications on PowerPC Macs long before any third party application does.
I guess the point of this is just me wondering why anyone would bother to spend money on a "forced" upgrade to their software and plugins just so they can run them natively (or at all) on their new ICBM when they can just buy a PC running Windows along with the same software they'd have to purchase either way for Mac OS X. Especially for software like Adobe Photoshop, software that many users choose the Mac for because Photoshop is optimized for the PowerPC and is thus faster for most things on a PowerPC. As it stands the PPC version of PS runs much, much slower under Rosetta and the "maximum speed" PS can run on the Intel x86 architecture is already available, and has been for some time, on Windows. If you're a manager or another person in charge of an Enterprise, Business, or School these are all things you may have to consider before making a future purchase. And sadly, doing what is cost-effective in the long run is not always the same as doing what is the best for users.