ConFoo is one of the most important developer-oriented conferences and includes Ruby content. ConFoo 2013 will be held on February 25 through March 1 in Montreal, Canada. The team just opened its call for papers. Candidates can submit proposals until September 23. Consult the call for papers page for details and to start submitting. You can even get advice on how to write proposals. The call for papers is public, meaning that all proposals get published on the website for others to vote and comment on. This approach allows the organizers to pick subjects that have most interest in the community. The comments are only visible to speakers and organizers to avoid influencing the votes.