Quite often my Og managed objects (Entities) include an attribute that takes enumerated values. I use the following code snippet to augment Nitro's form generation helper to render a usable control.
TYPE_VALUES = Dictionary[ TEXT = 0, 'Article', IMAGE = 1, 'Image', VIDEO = 2, 'Video' ] attr_accessor :type, Fixnum, :control => :options, :options_data => TYPE_VALUES
This code uses the Dictionary class from the Facets library. I hope you will find this useful as well ;-)