failed to push some WTF?

csv_renderer.gemspec

# Provide a simple gemspec so you can easily use your enginex
# project in your rails apps through git.
Gem::Specification.new do |s|
  s.name = "csv_renderer"
  s.author = "Mark Bennett"
  s.email = "mark@burmis.ca"
  s.homepage = "https://github.com/MarkBennett/csv_renderer"
  s.summary = "A Rails3 renderer for the Comma Seperated Value (CSV) format."
  s.description = "A Rails3 renderer for the Comma Seperated Value (CSV) format.  Thank-you to @josevalim for his excellent Crafting Rails3 Applications book which inspired this gem."
  s.files = Dir["lib/**/*"] + ["MIT-LICENSE", "Rakefile", "README.rdoc"]
  s.version = "0.0.1"
end

gem push

~/versioned/csv_renderer[master*]: gem build csv_renderer.gemspec 
WARNING:  no rubyforge_project specified
  Successfully built RubyGem
  Name: csv_renderer
  Version: 0.0.1
  File: csv_renderer-0.0.1.gem
~/versioned/csv_renderer[master*]: git push csv_renderer-0.0.1.gem
error: failed to push some refs to 'csv_renderer-0.0.1.gem'

The code in this example is all coming from this repo. https://github.com/MarkBennett/csv_renderer