Use Zero Install packet manager
Roland Taylor commented
We would rather use a more standard method than 0-install or autopackage, so we'll stick with debs and rpms. Other distro users can package from source in their native formats easily.
Sry guys, didn't know that click on "vote" submits the form.
Here the description:
Zero Install is a decentralized packet manager. If you use software with Zero Install it has no side effects to the system. To launch a software, you just type in an internet url and it will be transfered to your system. To make a software ready for Zero Install you just have to describe the software (e.g. where to download, which dependencies it needs) with an xml file, called feed. For each new version you just have to register it to the feed. If the user starts the program the next time about Zero Install, it updates automatically.
At the moment I provide such a feed for Pinta on http://0install.de/feeds/Pinta.xml .
I really recommend you to read more about Zero Install on http://0install.net/ . To provide a feed is really simple. The updating of the feed could be added to your release script.