Rails needs to do a release solely focused on speed. Dropping 1.8.7 is a good step for a lot of people, but I feel Rails itself has gotten slower since 2.x and I know a lot of people would agree with me.<p>I do a lot of work in CodeIgniter as well as Rails (w/ Ruby 1.9.2 in production), and there's no doubt that my CodeIgniter apps <i>on slower servers</i> with little-to-no deliberate optimization are faster than my Rails apps.<p>For just one particular example, I have found rendering partials in Rails are such a point of poor performance that I have often found myself avoiding it.<p>There's this red herring (and a pet peeve) that making the framework 'less bloated' by dropping components or making them optional equals performance. You'll even see a comment on this blog post asking which components to remove to improve performance! It doesn't work that way when the core components of Rails remain slow.<p>While the speed of Rails had Ruby 1.8.7 to blame for a long time, now that it's being dropped I think 4.0 has a unique opportunity to optimize for 1.9 and make a big difference to the overall speed of the framework.