[jebblue]

Totally agree, UI's do not need to be overseen by an overlord of design. I can right now start up a KDE app or a Gnome app and they happily co-exist. Try to pull of something like that on oh Windows, Mac or Android. At least I don't think I've ever seen anything like that on those OS's.

[xtracto]

The problem I see with open source applications (on the GUI level, for *BSD and Linux families) is that of interaction between apps.

Something as obvious as copying and pasting between applications is still broken in these systems mainly due to the lack of a standard, or for the small standards that exist, few applications follow them.

I think that one of several issues, but it is the one that I find more obvious.

[jodrellblank]

Something like running a Win32 app, a .Net Winforms app, a Java app and wxPython app concurrently?

[jebblue]

Good points. Even Gtk apps now that you jog my memory.

[wmf]

OS X had Cocoa, Carbon/QuickDraw, Classic, and X11. It's great for compatibility but not so much for consistency.