I couldn’t have written it better.

The only disagreement I’d have is that Win2k was the major turning point when NT architecture hit mainstream. Suddenly we had NT core with a UI that users understood and dynamic events (PnP).

Though for us in IT, NT4 was the major turning point - a solid OS that you could actually use in business.

XP brought a lot more user functionality (plus better performance), and Windows 7 brought the current version of 64-bit architecture.