Senior (enterprise)

    Analyse and profile an application for performance and memory issues
    Analyses and profile an application for security issues
    Understand database modeling and query analysis
    Tune a production deployment (Passenger, Thin, Apache etc)
    Understand and use Ruby metaprogramming
    Mentoring skills
    Communication skills
    Planning and Estimation

Mid-level (startup and mid corp)

    Setup and deploy a Rails App for production
    Understand the Rails stack - callbacks, filters, plugins, engines, gems, rack
    Understand and use Active Record associations
    Understand and use scopes to define model abstractions
    Define tests using Cucumber and rSpec
    Understand and use Object Orientation
    Understand and use Design Patterns (explain what they are, know some basic patterns)

Entry Level (rails beginner)

    Create and setup a Rails environment
    Use generators to create models, controllers and migrations
    Create and use a migration to manage the database
    Create a unit test using rspec/etc
    Create a model and basic validations
    Handle a GET request using a Controller, Model, and View
    Handle a POST request using a Controller, Model, and View
    Basic HTML, CSS and JavaScript
    Basic GIT - clone, commit, push