Yes, just install pantheon-session-bzr from the AUR. You may need to edit some PKGBUILDs to use plank-bzr (thats what I am using) or to use pantheon-dock. Itīs a mess at the moment, some needs plank-bzr and some needs pantheon-dock. I recommend you to install some indicators-. You will find some of them in the AUR and some from the unity repository (you can find it in the forum). Let me know if you need any help.