The toolbar icons at the top of the workbench window would have a background/border colour change in Eclipse Juno (F17) to indicate that a particular icon was being selected/clicked. Now, only the dropdown list arrow seems to have any sort of change for the icons. I'm not sure if this is a problem with SWT, or maybe the underlying system libraries we use in Fedora.
I'm seeing this on GNOME. (I have an F18 VM with KDE and can see the hover/click actions changing the icon).
It looks like https://admin.fedoraproject.org/updates/gnome-themes-standard-3.6.5-1.fc18,gtk2-2.24.16-1.fc18?_csrf_token=2426a191ccce4c3e20bf6c5f16c6b121047c4ec2 will fix this issue.
This bug is similar to Bug 906556 , in that both are UI bugs that required an update to the same component to be resolved. I'm marking this as closed now.