Yes, Apple is a hardware manufacturer that happens to make it's own OS (something that Dell or Lenovo could do any day if they could get off the MSFT/INTC gravy train - by creating their own Linux distro).

Switching models to compete with the Windows model is a mistake they were lucky to make once and live to tell about. They will not make that mistake again.

If you're looking for competition against Microsoft, look to Google. Both of these companies aren't hardware companies at their heart, and both want manufacturers to bundle their OS.

I'd say that if Microsoft had an ally, it would be Apple today (only in the sense that Apple doesn't care for Microsoft's business).

No, by "breakthrough" I mean support common x86 devices, which OS X does support to a limited degree.