I currently have Faye working with my Rails 3.0.9 application. However I have two separate tabs open in my terminal. One for the Faye server, and one for the Rails server. H
Nowadays, I'd just use Foreman for this: https://github.com/ddollar/foreman
By creating a Procfile, you can specify which daemons need to run (with control for how many of them of each you want), and keeps everything in one terminal window (with great color coding of each process). It can even export to upstart or init.d scripts for production, if your environment is debian based.
Once your Procfile is all set up, then all you need to do is run: foreman start and you're off to the races. I use it for resque and faye.