At the last Macworld Expo held at the end of January, Apple launched its first computers based on Intel processors. The only problem: Intel-based hardware arrived before many programs had been rewritten for compatibility with the newer processors.
In order to ensure the smoothest possible transition, Apple developed an emulation technology called Rosetta which allowed any application designed for PowerPC to run on computers with Intel processors (in exchange for a significant performance impact). . Thus, while a program written natively to support Intel processors could run faster on a MacBook Pro or Core Duo iMac compared to the speed it would get on a PowerPC-based computer, applications that running in Rosetta were generally slower, and even more so when it came to processor-intensive applications such as Photoshop.
Today things have changed substantially since the release of the Mac OS X 10.4.8 update. Systems based on Intel processors have achieved a significant improvement in tests performed on Photoshop and Office, with ranges ranging from 3 to 36 percent. Photoshop’s figures have seen even greater improvements when the application has been run on a 2.66GHz Mac Pro / Quad.