I don’t use iTerm and I don’t use tabs and I don’t use screen. I just keep as many Terminal.app windows open at a time as necessary, and rotate among them with command-`.
Holy bloody crap. Not that he doesn’t use iTerm, but the command+` thing. I didn’t know. For years, I have been using Witch, which is a fine app, but is painfully slow on my old Powerbook. Thank you, Tim Bray, for enlightening me.