Dependancies are where a package uses code or data from another package, ie it "depends" on the presence of that package. GnomeICU relies on the presence of GTK (widgets), which in turn relies on GLib (c utility code), GTK also relies upon Xlib, and they all rely on libc.
Dependancy graphs are scary
For RH8 no, not really, you might want to try Synaptic if you have apt, but it's hardly well integrated
This is a big issue with the rh8 series, they do know about it. RPM generally sucks for net based distribution of software anyway.