The history of Apple's 64-bit transition and how it got disturbed by the Intel transition

Apple started the transition to 64-bit with the release of the G5 in 2003. Unfortunately it got disturbed by the Intel transition. Here is a timeline:

• June 2003: Apple releases the 64-bit Power Mac G5, shipping it with the first G5-capable version of Mac OS X that supported only 64-bit physical addressing.
  
• September 2004: Apple releases the 64-bit iMac G5.
• April 2005: Apple released Tiger, adding support for 64-bit command-line apps.
• June 2005: Apple announces the Intel transition.
• January 2006: Apple releases the first Intel Macs with a 32-bit-only Core Duo processor (of course shipping them with the first 32-bit-only Intel version of Mac OS X 10.4), downgrading the iMac to 32-bit.
  
• June 2006: Apple announces the Mac Pro with 64-bit Xeon processors (of course shipping them with the later 64-bit capable Intel version of Mac OS X 10.4).
• September 2006: Apple releases the Core 2 Duo based iMac, upgrading it to 64-bit again.
• October 2007: Apple releases Leopard with 64-bit GUI application support.
• June 2009: Apple announces the Intel-only Snow Leopard with a 64-bit kernel.