Been using iTerm for a while in Mac OS X in place of the default Terminal.app. Really neat little app. You can set all sorts of colors, make the term's background transparent, and have mutltiple tabbed terms open in the same window. A little slow on the draw sometimes, but neat over.

That said, I've stopped using it for Apple's X11. For some reason, both Terminal.app & iTerm have real problems with some "command line" apps (ncurses stuff). The xterms in X11, however, do just great with ncurses, come up faster and act more responsively than iTerm or Terminal.app, and has to be open for me to run, say, Abiword anyhow.

That X11 ships with 10.3 (apparently) is good news. It should replace Terminal.app on OS X.