The Ubuntu Packages Search page has been updated to match Ubuntu's new branding scheme introduced back in 2010. According to the fine folks over at OMG Ubuntu!, this area of the Ubuntu website is one of the last areas to get updated.
What does this website do?
Linux users are accustomed to acquiring software from software repositories accessible through a pre-installed application. In Ubuntu, this application is the Ubuntu Software Center. In openSUSE, this is the Add/Remove Software section of Yast. In Fedora, this application is simply called “Software.”
If a Linux user isn't at their computer, they don't feel like opening up another application just to quickly check to see if a desired piece of software is available, or if they want to know what software is available in a new distribution before making the switch, they can simply search the same software repositories using package search websites. Ubuntu has the Ubuntu Package Search page, Fedora has the Fedora Package Database, and openSUSE has a package search section on its download page.
Who is this page intended for?
The Ubuntu Packages Search page is a useful tool for more technically minded users who are more aware of the underpinnings of their chosen operating system. New users will probably have an easier time getting around the Ubuntu Software Center itself, for it avoids the technical language that can be found all throughout the Ubuntu Packages Search page, and it provides a straightforward means of installing software.