- International text input: I can't remember the last time I had to use accents or special characters not in my native language; a few greek letters for formulae, and generally I can use '/alpha' instead of α. Isn't having to use chars not in your language pretty uncommon?
- Trackpad quality: yes, I love using Macbook trackpads, but I use the mouse/trackpad very little anyway, and isn't something I find useful enough to miss much.
- emacs keybindings: sounds fantastic, but a) not many people use them and b) don't know if they'd be that great for Vim-ers like me.
Even if there are a lot of things that Mac might do better than Windows and Linux, I agree that the popularity of so many cross-platform tools and the web have nullfied a huge part of it.