I think Twitter is pretty fast and I bet most of the service's users do as well. Pretty fast is never good enough, however, so the microblogging site has gone back to the drawing board to make it even faster. The updates being implemented today are going to make Twitter faster than a file download in South Korea.
For a bit of background first, Dan Webb, Engineering Manager at Twitter, explains that the last major update to Twitter back in 2010 pushed all of the rendering onto the user's browser. It helped speed along some processes, but there are some things that only a server can accomplish. That's why the new Twitter is moving rendering back to the server. The most immediate change is that initial page load times should be one-fifth of what they were.
Twitter will continue working on improvements to make the site faster in the coming months. It's an exciting time for Twitter from both a user and developer point of view. The user gets the increased speed and developers get to see some exciting work from one of the biggest friends of the open source community.