By Zach Spear

Published: 10:00 AM EST

Apple is slowly dropping PowerPC compatibility with its latest software releases as evidenced by a major new feature of iLife '09 that will function only on Intel-based Macs.

Ars Technica points out that GarageBand's Learn to Play, a new section within the music-making software that serves as a digital instructor for a user learning a new instrument, is not officially supported for Macs still running on PowerPC processors.

System requirements found on the Apple Store website say, in fine print, "GarageBand Learn to Play requires an Intel-based Mac with a dual-core processor or better."

When iLife '09 was first announced at last month's Macworld, the system requirements included "a Power PC G5 or 867 MHz or faster PowerPC G4" without mentioning any incompatible individual features.

Learn to Play also offers Artist Lessons from a Lesson Store built into GarageBand where artists teach fans how to play their hit songs on certain instruments for $4.99 each lesson.

Chief executive Steve Jobs confirmed the switch from PowerPC to Intel in June 2005, targeting the end of 2007 for the transition to be completed.

Mac OS X Leopard excluded slower PowerPC-based Macs with a cutoff set at 800 MHz G4 or faster.

Official documentation from Apple gives clues that PowerPC Macs very well may be left out completely when Mac OS X 10.6 Snow Leopard is released sometime during the first half of this year. Developer copies distributed at WWDC last year included a requirements PDF that listed "an Intel processor" as the minimum necessary to run the software.

Adding further weight to that possibility, people familiar with the ongoing development of Leopard have previously told AppleInsider that Snow Leopard would in all likelihood exclude support for PowerPC processors.