fwiw, postgresql 9.2 supports a json datatype. you can efficiently access/query json fields using plv8 (http://code.google.com/p/plv8js/).

so you could have:

  create table form_results (                                                                                
    id serial primary key,                                                                            
    data json                                                                                         
  );

http://pgeu-plv8.herokuapp.com/ has more information.