As of today Weston is available in Debian sid/testing, and it is very usable, at least for me with an ATI card. I have been tinkering with it a bit. One of the things I did was to switch to a german keymap (see man 5 weston.ini and /usr/share/doc/weston/).
Several gtk applications are usable if you install libgtk-3-0 from experimental. However, doing this is not recommended, so I won't describe the necessary steps.
You can simply launch weston from inside X, or use weston-launch from the console. For the latter, check the README.Debian in the documentation.
Having a terminal is certainly nice, but especially if you want to do more than just that knowing the keybindings is useful. That list doesn't mention workspaces yet, but it's basically super + F<workspace number> or super + <up|down> to switch workspaces, and super + shift + <up|down> to move the focused window to another workspace. I'm sure there are more keybindings I haven't figured out yet.
Installing a web browser
I was also very pleasantly surprised that the packaged web browser dwb runs fine inside Weston. I tried epiphany-browser as well, which uses gtk3, but it segfaults.
Dwb is a little hard to use, buy you might even like it if you prefer keyboard-based controls.
A few additional steps are necessary:
# apt-get build-dep mplayer
This failed for me due to conflicts. If you're having problems as well try to manually clean up the list obtained with apt-rdepends --build-depends --follow=DEPENDS mplayer.
Additionally, I also had to install the following packages:
# apt-get install libwayland-dev libxkbcommon-dev libegl1-mesa-dev libavresample-dev
After this building mplayer was straight forward for me:
$ ./configure --prefix=$prefix --enable-wayland --enable-debug --disable-x11 $ make install
With a working terminal, web browser and video player weston is very usable for me. I'm not very happy with the window management, but I guess that was to be expected.
As you can switch to a different tty and run weston-launch there it's also possible to run xorg and weston simultaneously.