When talking to Raimonds Simanovskis the other week, I convinced him to sign up to give an OpenWorld Unconference session. Raimonds is the maintainer of the enhanced Oracle Adapter for Rails so this session should be excellent.
His talk "Using Ruby on Rails with legacy Oracle database" is on Thursday at 10pm, Moscone West 3rd Floor.
All unconference sessions are listed at http://wiki.oracle.com/page/Oracle+OpenWorld+Unconference. There are still slots open.
Other Rails activity at OpenWorld includes an interesting session on Rails and Oracle Mix at 1pm Monday (Marriott Salon 14/15), and a Hands on Lab at 2:30pm Tuesday (Marriott Golden Gate B1).