The main benefit I get from Awesome is having 9 workspaces ("desktops"). I use my mod key (in my case CAPS but it can be Alt or anything) plus # to get to any workspace. I have web browser on one desktop, email on another, IM on another, terminals on another, programming on another, and it's really, really easy to switch around. This was a HUGE improvement for me over Windows (and even Gnome), just in terms of managing multiple windows/applications running at once.
Also nice to be able to get two windows to share the screen with a keystroke, if I need to look at two things at once. And in the same vein, tiling is really nice for IMs, because on the workspace for IMs, I can see all my chats at once. Normally for other tasks, like web browsing, I just switch into the tiling "mode" that doesn't tile (i.e. application is "maximixed").