Apologies for reviving a dead thread, but I wanted to add one thing:
I see a lot of comments saying that the difference between a tiled window manager and terminal multiplexer is obvious, but I don't think that's true at all, especially to a new unix user. On an abstract level, they both multiplex screen space so that it can be shared by multiple clients. And they even do so using a nearly identical tiling paradigm!
The fact that on a modern unix there is a strong divide between X11 apps and CLI apps is kind of nonsensical. For example, see the design of Plan 9:
http://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs#Graphical_programs In it, a lightweight window manager is part of the base system, and graphical apps can just replace the shell they were launched from.
Anyways, I just wanted to add my newbie friendly 2¢.