jacobolus wrote: Without thinking too hard (or I might come up with something else), I think the Dock might just be the single worst thing about OS X.
Mac OS 9 was really consistent. Clunky, but consistent.
Mac OS X started disintegrating this consistency. Other old fogies will remember that Macintosh services (the faceless background applications — 'appe' files) would crash the GUI if they accidentally opened a regular window that could take focus.
Unless something has changed in the last couple of versions, Mac OS X considers it normal to have regular windows that are not owned by an application, for example Spotlight results. They don't show up in Exposé, and they can't be reached using cmd+tab, as that only selects applications. You have windows that, so far as the keyboard are concerned, don't exist.
Exposé always used to (and may still, I don't know) have a fault where a sheet window and its parent could be selected independently in all-windows view. Sheets within sheets are considered wrong, but perfectly possible (there's a program in Mac OS X that does it). There are situations in which sheets spawn pseudo dialog boxes that are owned by another process, and either these get set to always-on-top (thus blocking other programs you switch to), or they just vanish when you cmd-tab or use Exposé to return to the program you were in.
The whole UI lost its sense of immaculate consistency and I've never felt that Mac OS X's UI actually makes any sense. The indefeatable Dock got on my nerves too, as I wanted to replace it with the far, far superior A-Dock X.
So much of Mac OS X is just completely, utterly broken. There's an installer system (packages), but no corresponding uninstaller. There's no way to just run programs — I have Agar Sagoo's Namely on my old Mac as I can start programs so much faster with Namely than Spotlight.
Animations are mandatory, despite the fact that, if your brain is reasonably fast, all animations achieve is make you wait for the computer to catch up with a simple request. Animations are powerful for non-technical folk as they avoid the problem of humans not noticing instantaneous changes, and they help tie chages back to an action or source, but an "off" option is still important. The only exception is the file/program launch animation as it is non-blocking (in Mac OS 9 it was blocking).
And indeed, the Dock is rather odd.
I loved Mac OS 9, and X was never the replacement it should have been.