On Nov 24, 2008, at 2:10 PM, Ted Gould wrote:

http://en.wikipedia.org/wiki/Mac_OS_X_v10.5#System_requirements

Machines without G4s? Those without DVD drives?

Seems the first G4 processors were in Summer of 1999:

http://en.wikipedia.org/wiki/PowerPC_G4#PowerPC_7400

I think the last shipping G3s were in the iBook with the iBook G4

shipping in Oct. 2003.

http://en.wikipedia.org/wiki/IBook#iBook_G4

I think that 5-years is a reasonable deprecation time for hardware

running the latest version.

No, machines that customers did not shell out extra money to get the latest and greatest OS.

Going into this past summer, some reasonable estimates had 10.5 only hitting 30% adoption, with 10.4 still holding about 60%.

Remember, the upgrade cycle is a little different than Linux, since one actually has to pony up cash to move forward.

Also businesses are a large factor. I'd done some research for work and it turns out that a lot of businesses are not upgrading to 10.5, so for anything targeting the enterprise support for 10.4 was a must.