I only have a PPC one, and as I was so disappointed with Apple (like: slow GPU, bad ATI drivers, no way to install a new driver, no way to put in a GOOD graphics card, bad user interface that doesn't even let me resize windows anywhere but at the lower right corner and that can't even maximize windows), I won't ever get a Mac again.
So yes, what you suspect may be true. If it can be "officially" verified, we could change the default of the option to 0 on Intel and 1 on PPC. Don't want to base this on guesswork though.