Yahoo UI Library with Rails

I realize this is an old thread, but has anyone had any success with the
Yahoo UI library?

We used it on Lingr, when we were developing it: http://lingr.com --
which is a Rails app.

I'm planning on using it with RoR (and PHP) and would like to know if
anyone ran into issues with it (like browser compatibility, etc.).

We didn't run into any real issues with it. We decided not to use it
in the live app because the libraries are _large_, and we only needed
a small amount of the functionality. So it made more sense to write
our own code for the few things we needed done (like the login
dialog).

My experience with the YUI libraries was generally quite positive
though. Very powerful and well thought out.