One of the things I utterly hate about Windows is when you turn it on, 50 companies software updater programs instantly start up, deluge you with alerts and kill your machine for several minutes.
Linux distros, on the other hand, have software updater's that include all sorts of software, not just the operating system. Some, Like Debian & Ubuntu, can get software from multiple sources.
This is how both Chrome & Dropbox on Ubuntu work: they install & add the companies servers as repositories. From then on it updates through the same procedure as the operating system. Brilliant.
Think long and hard before doing anything different. Installing your own sofware updater on my Linux box will count as a major, major negative against you. Seriously, I can't think of a single software package that does this on Linux.