The antiphons to the psalms have been updated and should now sound more familiar to many people. Various other minor corrections and improvements have been made.
If you are using the Universalis web pages or email service, these things have happened automatically and there is nothing that you need to do.
If you are using the iPhone / iPad / iPod Touch version then the update should become visible in the App Store once Apple have approved it, probably in just over a week. Like all the other updates, you will be able to install this one free of charge.
If you are using one of the other downloads, please visit http://www.universalis.com/n-download.htm and follow the appropriate link to download and install the latest version. You shouldn't need to re-enter your registration code after doing this.