Microsoft officially releases Windows XP next week; Apple's release a few weeks ago of OS X's upgrade 10.1 marked its real beginning. Why X? To signify the unknown: a future in which users may experience (no pun) a consistent powerful interface with few crashes, lots of help along the way, and a general lack of the irritants of all previous consumer OS's. I'd be very interested here (click comments) or via email to hear people's first reactions to both systems.
I'm not in the camp of "Microsoft stole this from Apple" or vice versa. A lot of developments in both systems come out of what people need from their computers, and what both companies were finally able to achieve: seamless digital media exchange (digital cameras, music, video); non-crashable OS (mostly); pre-emptive multitasking and multithreading (one program doesn't hold up another and all share in a round-robin of processor power); consistent, pretty, powerful interface.