I'm guessing you're referring to the media server, but you might alternatively mean the object-relational mapper (which could probably run under Mono or Portable. Running these commands will upgrade all such software to the latest versions provided in your configured software sources: flag.
Unlike most software for Ubuntu, Subsonic doesn't have a software source you can set up to provide it, so that's the way you have to install it.
If you’re familiar with torrents and have an ISP that doesn’t limit them, you can download the upgrade much more quickly.
You’ll also be sharing your bandwidth with other Ubuntu users and helping to reduce the load on the servers, which is especially beneficial on release days when the server overload causes problems.
Renewing the Installation without formatting the partitions (in contrast to upgrading), will also keep the personal data and configurations under /home but will renew all system settings under /etc as well as the default set of installed packages.