Rails' ActiveModel#create returns truthy value even when the model is invalid

bug.rb

gem 'activerecord', '4.1.0.beta1'

require 'active_record'
require 'minitest/autorun'
require 'logger'

Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)

ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:')
ActiveRecord::Base.logger = Logger.new(STDOUT)

ActiveRecord::Schema.define do
  create_table :posts do |t|
    t.string :title
  end
end

# *** Actual bug related snippet

class Post < ActiveRecord::Base
  validates_presence_of :title
end

class BugTest < Minitest::Test
  def test_save_return_value
    assert_equal false, !!Post.new.save
  end

  def test_create_return_value
    assert_equal false, !!Post.create
  end
end