Complex sentence: On December 23,2008, Merb, another web application framework was launched, and Ruby on Rails announced it would work with the Merb project to bring "the best ideas of Merb" into Rails 3, ending the "unnecessary duplication" across both communities.
Split into simpler sentences: On December 23,2008, Merb, another web application framework was launched, and Ruby on Rails announced a commitment to work together. The Ruby on Rails team announced they would work with the Merb project to bring "the best ideas of Merb" into Ruby on Rails 3, ending the "unnecessary duplication" across both communities.