I'm a bit bothered by the systray icon.
On Mac OS X, the application will stay in the Dock anyway so I find
the systray icon a bit of unnecessary noise. Besides, the Menu Bar
Extras space is a bit limited. As far as iChat, Skype and Microsoft
Messenger for Mac 8 Beta go, they don't display a systray icon by
default and (at least the first two) have preference check boxes to
explicitly enable its display.
Ubuntu is, of course, more complicated. But I've already been there on
the subject that I'd personally like us to support indicator apple and
indicator applet session rather than have an icon in the notification
area. GNOME HIG, of course, advises against using the notification
area so indicator apple and indicator session applet support should be
a welcome addition on Ubuntu.
Windows is slowly becoming terra incognita for me because I don't have
access to it but, if I correctly remember what I've seen in Windows 7
RC and what I've read, Windows 7 takes yet another step at trying to
solve the systray overcrowding by introducing Dock-like taksbar items.
Do you think it will be worth it to add an option for the systray icon
at least on Mac OS X so that it can be displayed or not displayed
depending on user choice?